Simulating full-auto fire in RPGs?

[Altair_the_Vexed]

Help!

I'm British (that's not the only reason I need help), and never done military service, so I know little about firearms - except that they're a staple of modern action fiction, and that'll include RPGs.

Some RPGs deal with the indiscriminate nature of auto-fire poorly - for example:

d20 modern adds small bonuses to hit, and increases damage (which you need to take feats to achieve), or treats the auto-fire as an area effect which first requires an attack roll (against a low DC), and if it hits, it can still be dodged, and only ever deals the base damage of the weapon.
CP2020 makes auto-fire almost the best action you can take: you get a bonus for every 10 rounds, and deal 1 hit for every point over the DC you roll.

What elegant and realistic enough ways have you guys and gals seen to simulate the hail of lead that comes from fully automatic weapons?
There must be something between the extremes of useless, overcomplicated, or so-good-you'd-never-do-anything-else.

[Actana]

Star Wars Saga handles fully automatic weapons as an 2x2 square area attack with a -5 penalty with enemies taking half damage on a miss. There are also feats that allow you to direct the fire against a single target, dealing 2 dice more damage (for example, a blaster rifle deals 3d8 normally, and 5d8 with the feat).

For a d20 system, it's decent enough of a mechanic in my opinion.

[Seerow]

Shadowrun's full auto lets you choose: Narrow Burst (very high damage because you're aiming all bullets directly at one point, but harder to hit because recoil drops your accuracy) or Wide Burst (deals same damage as an average shot, but since you're spraying in a wide arc, targets get a massive penalty to their avoidance roll, making you more likely to hit despite the recoil).

You can also make the choice to use suppressive fire, which automatically deals lower damage to everyone within an area who isn't taking cover.

[Slipperychicken]

Shadowrun 5e (a diepool system) has burst/semi/full-auto subtract from the target's defense pool. This is balanced by imposing recoil: every bullet you fire adds 1 to your recoil penalty, which can quickly get out of control if you aren't careful.

nWoD (New World of Darkness, also a diepool system) gives a bonus to hit, but puts penalties on top of it for each enemy you target after the first. Long burst gives +3 to hit, -1 per enemy after the first. Medium burst gives +1 to hit, -1 per enemy after the first.

Pathfinder (a d20 system) made it a line attack, targeting every creature in the line, although at -2.

[CombatOwl]

Help!

I'm British (that's not the only reason I need help), and never done military service, so I know little about firearms - except that they're a staple of modern action fiction, and that'll include RPGs.

Some RPGs deal with the indiscriminate nature of auto-fire poorly - for example:

d20 modern adds small bonuses to hit, and increases damage (which you need to take feats to achieve), or treats the auto-fire as an area effect which first requires an attack roll (against a low DC), and if it hits, it can still be dodged, and only ever deals the base damage of the weapon.
CP2020 makes auto-fire almost the best action you can take: you get a bonus for every 10 rounds, and deal 1 hit for every point over the DC you roll.

What elegant and realistic enough ways have you guys and gals seen to simulate the hail of lead that comes from fully automatic weapons?
There must be something between the extremes of useless, overcomplicated, or so-good-you'd-never-do-anything-else.

The problem is that they kind of are complicated to model in a tabletop game. Setting aside the conflict between what automatic weapons are actually used for and what players expect they ought to do, there is an actual complexity in trying to model what a whole lot of bullets do.

Hardly any rule system does it well, and none of the ones that do handle it well are simple. To be honest, an abstract approach is usually a lot better in terms of gameplay, even if it's not very accurate.

The only tabletop game that I've seen that actually does a reasonable job at accuracy is GURPS, and it is quite complex (declare how many shots you're firing beforehand, this gives you a bonus on the roll to hit, for every full recoil multiple by which you make the shot, you score an extra hit). Because GURPS does gun damage based on the ammunition rather than the weapon, it's relatively easy to score damage (still complex--it's GURPS after all). Automatic weapons get a whole pile of extra rules about attacking areas, doing suppressive fire, etc.

Shadowrun 5th edition kind of takes the same tack, but they screwed it up like much of the rest of the combat rules.

[Actana]

If you want a full simulation on automatic weapons (and small arms in general), check out Phoenix Command. It's from what I know pretty much the most realistic small arms simulation game out there. But having not played it or even read the rules, I can't say anything concrete.

[Erik Vale]

One's I've seen.

Heroes: You get to a attack, noting the number of total attacks you wish to take, which is any number below or equal to the weapons autofire number [normally, some must be equal]. For every two you hit by, you hit an additional time.
This way, you can potentially do lots of damage if you get lucky/are really good [i.e. guy stands up and is suddenly hit by a hail of bullets, you fire a birst into a crouching baddy behind cover's head.] or very little/none [recoil means you shoot around/next to the guy hitting maybe once], however it's strictly better than firing lots of individual shots, where all the shots get a penalty of [shots taken-1]*2, and first miss prevents the other attacks.

Mass Effect RPG based on d20 system:
You get to make up to your autofire of attacks, at your recoil penalty [so for a SMG, maybe 4 for up to 10 attacks]. You can do this twice for the second set to have -2* pen, or three times for the third set to have -3*pen, so you can burn through huge amounts of ammo to spray a area, but your unlikely to actually hit anything with later attacks without a lot of luck/skill.

[jaybird]

Dark Heresy has a nice autofire system. For every 10 you beat the target number by on a d100 you gain an extra hit, up to the number of rounds consumed from the magazine by autofire.

[Tengu_temp]

In Mutants and Masterminds, Autofire is an extra for items and powers. It lets you attack several enemies at once, at an attack penalty equal to the number of enemies, if used against a single enemy it deals the more damage the more you beat their AC with your attack roll, and it lets you lay cover fire to cover your allies and suppress your enemies. Pretty elegant.

[Mr. Mask]

....All of those systems seem needlessly complicated. Why not just roll for each shot?

[Seerow]

....All of those systems seem needlessly complicated. Why not just roll for each shot?

Rolling for each shot takes less time to explain, but is more complicated in terms of time taken to resolve the shot at the table, and generally more overpowered as well.

[CombatOwl]

....All of those systems seem needlessly complicated. Why not just roll for each shot?

Because that is neither accurate nor simple? Say you're in d20 modern. Why should each bullet have an equal chance of critically wounding someone or going so far astray as to have no chance at all to hit? All of your shots are grouped nicely... except that one shot that goes flying off in a random direction behind you, somehow, because it was a fumble?

If you're firing a burst at something, those shots should generally be grouped somewhere at least loosely together. Making independent tests for each bullet is the exact opposite of that.

[Mr. Mask]

Increase the penalty per shot.

[Seerow]

Increase the penalty per shot.

And now you're getting into adding rules that are going to make it just as complex as the other full auto rules, but still requiring many attack rolls (and thus longer resolution).

[Mr. Mask]

Not really.

[AMFV]

Help!

I'm British (that's not the only reason I need help), and never done military service, so I know little about firearms - except that they're a staple of modern action fiction, and that'll include RPGs.

Some RPGs deal with the indiscriminate nature of auto-fire poorly - for example:

d20 modern adds small bonuses to hit, and increases damage (which you need to take feats to achieve), or treats the auto-fire as an area effect which first requires an attack roll (against a low DC), and if it hits, it can still be dodged, and only ever deals the base damage of the weapon.
CP2020 makes auto-fire almost the best action you can take: you get a bonus for every 10 rounds, and deal 1 hit for every point over the DC you roll.

What elegant and realistic enough ways have you guys and gals seen to simulate the hail of lead that comes from fully automatic weapons?
There must be something between the extremes of useless, overcomplicated, or so-good-you'd-never-do-anything-else.

Realistically, having done military service, I can tell you that using automatic fire on a point target is probably a waste, and inaccurate as well. It's the reason why most military people are told to use a three shot burst, because accuracy drops off so much after the third shot.

Automatic fire on the modern battlefield is mostly suppressive in nature, it's to make somebody put their head down and restrict motion, not so much to kill individual targets.

The fundamental problem is that players are not going to expect that since most of them likely have seen the Hollywood hail of lead, and therefore will assume the other ideal is less realistic. In real life automatically firing a weapon will generally equal running dry in about 10 seconds.

[Seerow]

Not really.

Compare:
Roll dice 10 times, reducing chance to hit for each one consecutively.

Roll dice once at a reduced chance to hit, choose between reducing their dodge or increasing your damage.

You could make a similar comparison replacing the second entry with anything else someone has mentioned in this thread. The first is going to take far more time to resolve at the table, and most likely be less balanced, resulting in higher overall damage and more targeting flexibility.

[Mr Beer]

Not really.

LOL, this is just arguing for the sake of arguing. When you fire off 20+ projectiles in a round, how is it not mechanically tedious to apply a penalty and then make 20+ individual attack rolls?

Let's make it 4 PCs against 15 mooks, that sounds like a fun combat to roll out.

[Mr. Mask]

Seerow: Well, that doesn't sound like a good representation of auto-fire. You can give covering fire over an area, or shoot at a person. When you shoot at them you can use a reasonable number of shots, or turn your gun into an anti-aircraft weapon.

AC of 10, AC goes up by 2 with each successive shot. Roll, 9 miss. Roll 11 miss, Roll 15 hit. Roll 15 miss. Roll, 8 miss. Roll 12 miss. Roll 20, crit. Roll anything but 20, miss.

Now, there are a number of ways this can become the more complicated option.

If you need to record how much you roll over or under the amount of time goes up.

If applying damage from a given attack is complex, than more attacks means more time and facing that complication more.

If you're using a d6 system, the time counting the number of hits will increase the time.

If your method of increasing the penalty is more complicated than this, it adds complication.


Beer: If you prefer, I can say that I can see the point of your argument, and not discuss the subject with you.

Is that, twenty rounds per round, or twenty rounds per character?

[skyth]

....All of those systems seem needlessly complicated. Why not just roll for each shot?

The Original Top Secret game had you roll for each shot with a penalty for every shot after the first (That stuck around from round to round...You fired 5 shots each round, second round counts you as shooting shots 6-10).

[CombatOwl]

Increase the penalty per shot.

That's an awfully silly way to model it. We're not talking Rambo here, are we?

I agree that recoil should be a thing, but not the only factor here.

[Erasmas]

This is the way that I handle it in my modern setting (which is d20-based):



Some weapons have different rates of fire: single-shot, semi-automatic, automatic, and three-round burst. Single-shot attacks follow the above rules. A character who uses a semi-automatic weapon may make three attacks in one round. The first attack is at the character’s full attack bonus. The second shot is at a -2 to the attack, and the third is at a -4. A character who uses an automatic weapon may make five, using the same rules for a semi-automatic weapon. The second shot is at a -2, the third at a -4, the fourth at a -6, and the fifth at a -8. On a weapon that has a three-round burst setting, the character is allowed to make two attacks in one round (for a total of six bullets fired; three bullets per attack roll). The first attack is at a -2 and the second is at a -4. Be careful with this option, however… because while a successful attack can be devastating for an enemy (damage is rolled three times on a hit), a miss costs you three bullets! An expensive gamble… but with a big payoff.

[Slylizard]

Realistically, having done military service, I can tell you that using automatic fire on a point target is probably a waste, and inaccurate as well. It's the reason why most military people are told to use a three shot burst, because accuracy drops off so much after the third shot.

Automatic fire on the modern battlefield is mostly suppressive in nature, it's to make somebody put their head down and restrict motion, not so much to kill individual targets.

The fundamental problem is that players are not going to expect that since most of them likely have seen the Hollywood hail of lead, and therefore will assume the other ideal is less realistic. In real life automatically firing a weapon will generally equal running dry in about 10 seconds.

Agree with this 100% (I'm ex-infantry). There was only one moment I was ever told to use full-auto... that was when we were ambushed, the soldier who first noticed the attack would "drop a mag" (i.e. go full auto til he ran dry) in the direction he was shot at. Basically an attempt to force the ambushers to get their heads down.

Regardless, if you go full auto you'll run dry in seconds (modern rifle is typically 650-750 round/min). Plus your accuracy drops to being basically laughable.

Really, RPGs are incrediblely unrealistic in regards to full auto and are designed to follow movie rules rather than anything realistic.

[1337 b4k4]

Agree with this 100% (I'm ex-infantry). There was only one moment I was ever told to use full-auto... that was when we were ambushed, the soldier who first noticed the attack would "drop a mag" (i.e. go full auto til he ran dry) in the direction he was shot at. Basically an attempt to force the ambushers to get their heads down.

Regardless, if you go full auto you'll run dry in seconds (modern rifle is typically 650-750 round/min). Plus your accuracy drops to being basically laughable.

Really, RPGs are incrediblely unrealistic in regards to full auto and are designed to follow movie rules rather than anything realistic.

Which suggests that the best way to model full auto fire (as opposed to burst or semi auto) is as an area effect. So, to use a D&Dish description (with game terms that should be adjusted for your system in brackets):

Choose a direction. Until the beginning of your next turn, you project a [cone] of fire in that direction. Any character or creature starting their turn in, ending their turn in or moving through the area of effect must make a [reflex save] to avoid taking damage as though from an [attack of opportunity]. For every [5 feet] of movement through the area of effect, take a cumulative [-2] penalty to the save. This action consumes [one full magazine] of ammunition and you must [reload] before you are able to attack with the weapon again. If you take any other actions before the beginning of your next turn (such as [reflex saves]) this effect ends, but the ammunition is still spent.

That should do a fairly good job of simulating the suppressive nature of full auto fire, and be relatively uncomplicated in play.

[Airk]

Regardless, if you go full auto you'll run dry in seconds (modern rifle is typically 650-750 round/min). Plus your accuracy drops to being basically laughable.

Well hell, that's only like 60 shots per combat round! Why aren't we rolling each one individually? ;)

(Good god. I actually thought Mr. Mask was being sarcastic when I hit his first comment)



Really, RPGs are incrediblely unrealistic in regards to full auto and are designed to follow movie rules rather than anything realistic.

Working as intended.

[CarpeGuitarrem]

I dunno. Is full-auto fire ever effective in movies? Maybe when mowing down minions, but it almost always seems like it is used for suppression.

[Airk]

Obligatory (http://www.youtube.com/watch?v=9SW7-8C8kL4#t=1m54s)

[Berenger]

@AMFV, Slylizard:

In game terms: automatic fire should force the target to a) fall prone or b) take cover (represented by an easy or moderate reflex save), but rolling the save costs the target an action it could otherwise use to advance or return fire?

So, for d20 Modern:

1. attacker auto-fires at a number of squares and hits those squares
2. persons in those squares can choose:
a) stand upright and be hit for normal weapon damage if attack roll exceeds defense
b) sacrifice a move action or an attack action for the privilege to roll a DC 15 reflex save to avoid damage
3. if the reflex save was successful, the defender is in a prone position or behind cover and gets the appropriate defense boni as normal

[AMFV]

@AMFV, Slylizard:

In game terms: automatic fire should force the target to a) fall prone or b) take cover (represented by an easy or moderate reflex save), but rolling the save costs the target an action it could otherwise use to advance or return fire?

So, for d20 Modern:

1. attacker auto-fires at a number of squares and hits those squares
2. persons in those squares can choose:
a) stand upright and be hit for normal weapon damage if attack roll exceeds defense
b) sacrifice a move action or an attack action for the privilege to roll a DC 15 reflex save to avoid damage
3. if the reflex save was successful, the defender is in a prone position or behind cover and gets the appropriate defense boni as normal

Well in game terms for D20, I've not played D20 Modern, but I've played both Shadowrun and WoD as far as mostly modern settings go, and they're pretty terrible at it. Well that might work, although full auto without a weapon that's belt fed would give you about 6 seconds (1 round) before you are out of ammunition, actually around 3-5 seconds, which isn't the most effective tool for suppression, basically it's a last ditch "oh ****" moment.

[Rhynn]

No access to books right now, so I can't give details, but Twilight 2013 has hands down the best small-arms combat system rules, with the greatest realism:playability ratio achieved to my knowledge. IIRC it was very simple, though; apply modifier for number of shots fired, apply penalty for recoil (mitigated appropriately), random number of bullets hit. Also rules for using suppressive fire, etc.

[Tengu_temp]

....All of those systems seem needlessly complicated. Why not just roll for each shot?

Because rolling the dice 15 times when you fire a 15-bullet burst takes a crapload of time. And because many games, like nWoD or M&M or Fate, assume that you only get one attack action per turn, and all the numerous attacks you perform are just a part of that action.

[Rhynn]

Because rolling the dice 15 times when you fire a 15-bullet burst takes a crapload of time. And because many games, like nWoD or M&M or Fate, assume that you only get one attack action per turn, and all the numerous attacks you perform are just a part of that action.

:smallbiggrin: When we were around 13, we'd roll damage separately for every hit in a full-auto or burst attack in Cyberpunk 2020... with rifles, we're talking 7D6 per hit... and, of course, not understanding the rules we stacked all the damage before armor... assault rifles could bring down anything with one burst.

Rolling for every bullet doesn't make any sense to me, either, because not every bullet in a full-auto burst is even being sent at the target, realistically... there's better and faster ways to resolve it.

Also, anyone who thinks unloading all your lead as fast as possible is a great idea in Cyberpunk 2020 is playing with way too lenient of a GM. (Although the rules for how many hits you score are borked.)

[Mr. Mask]

Skyth: I think I've heard of that one in a discussion such as this before.


Owl: I'm afraid I don't understand what you mean. If you mean I didn't include other modifiers such as range, attack bonus and the like--those only need to be calculated for the first shot, then you add recoil to the target number with each successive shot. Anything after the 4th shot will require a crit.


Erasmus: I heard of doing burst that way somewhere before. Maybe it was from you that time as well. Now I need to wonder if it's technically accurate for burst fire...


Airk: Yeah, I should really have clarified on that...

Anything past the 4th or 5th shot, is noise. By the time you get to the tenth shot, there are more likely outcomes worth simulating than your bullets hitting a single-person target (lottery results).

Exceptions to that rule would have to be considered, though. The Vulcan cannon actually gets a little more accurate after the first few shots before its accuracy stabilizes to extremely good--and it shoots 100 rounds a second. Obviously, we need to roll 600 times with the same modifier whenever it is used.


Tengu: 15 shots a round is pretty reasonable. 15 shots per person I wouldn't call an attack action... "panic action," perhaps. A lot of troops do panic and go crazy with the rounds, of course.

When you get to mounted machine guns, and the Vulcan cannon, then it gets more complex. You can fire more shots effectively.


A Mind Forever Voyaging && Berenger: Looking at that, I really come to wonder about it. The sound of one of the German machine guns (...which one WAS it!?) had a reputation for making green soldiers duck, just from the sound of it going off. If the gun was firing in your general direction, even when the shots weren't going to hit you (this is very hard to judge in combat), you would find it very difficult to not duck for cover.

When soldiers counter ambushes with blind fire in the general direction of the enemy, it's a similar thing. The chances of taking out the given enemies with blind fire is low. The reason it's effective, is more to do with the psychological effect--and the fact that you don't know at the time whether you enemy is firing blind, or whether they've spotted YOU and are taking shots.

It's more like the example Beringer posted in some cases though, if you're suppressing a doorway which has Tangos on either side of it. If they pop out while you're suppressing, the chances of them getting hit is very high.

This matter like all of combat, is going to take a lot of work and headaches if you want to get a good simulation.

[GungHo]

Pathfinder and Saga are probably the simplest ways of doing it. Just treat it as an area attack. I'd probably go more for cones rather than squares or lines, but that's me.

Realistic with a man-portable weapon? "You missed." I wouldn't assign damage to anything but structures. I'd make one save roll to see if they were shaken/frightened for a round. Next turn. The only time I'd roll for damage is if someone in the party was standing in front of you. "Good job. You killed your friend. The enemy pointed and laughed. Next turn."

[AMFV]

Pathfinder and Saga are probably the simplest ways of doing it. Just treat it as an area attack. I'd probably go more for cones rather than squares or lines, but that's me.

Realistic with a man-portable weapon? "You missed." I wouldn't assign damage to anything but structures. I'd make one save roll to see if they were shaken/frightened for a round. Next turn. The only time I'd roll for damage is if someone in the party was standing in front of you. "Good job. You killed your friend. The enemy pointed and laughed. Next turn."

There are plenty of extremely effective man-portable automatic weapons. A SAW for example, easily man-portable, and it can be very effective if you're standing up when that thing shots you might have a problem, a 240 is even more effective and still man portable. A 50 cal, isn't quite man portable (requiring two mans to carry it) but it can still be fairly man portable. Cones are pretty effective as firing methods for automatic weapons and really you can't go into those areas because they are fatal, they're just known, basically it's battlefield control.

[Slylizard]

Which suggests that the best way to model full auto fire (as opposed to burst or semi auto) is as an area effect. So, to use a D&Dish description (with game terms that should be adjusted for your system in brackets):

Choose a direction. Until the beginning of your next turn, you project a [cone] of fire in that direction. Any character or creature starting their turn in, ending their turn in or moving through the area of effect must make a [reflex save] to avoid taking damage as though from an [attack of opportunity]. For every [5 feet] of movement through the area of effect, take a cumulative [-2] penalty to the save. This action consumes [one full magazine] of ammunition and you must [reload] before you are able to attack with the weapon again. If you take any other actions before the beginning of your next turn (such as [reflex saves]) this effect ends, but the ammunition is still spent.

That should do a fairly good job of simulating the suppressive nature of full auto fire, and be relatively uncomplicated in play.

This sort of thing is the most realistic I can think of. Basically using it as a suppressive cone or AoE.

To expand a bit on the theory (because why not?). The full-auto suppressive dump is really just the initial hit, it is expected that by the time you've dumped a mag, you have your mates all popping shots off in the enemies direction as well, thus maintaining a similar level of fire. This should therefore force the enemies to keep their heads down mroe than you, allowing your troops to break off, flank, and destroy the enemy.

But being that in game you can seperate combat into rounds, allowing suppresive fire to be an AoE suppressive effect... that's pretty reasonable.

AMFV is right about the limitations on portable weapons as well, in my experience, a typical section (10 guys) carried 8 rifles (30-round mag, 650-700 rounds/min), and 2 LMGs (200-round mag, 700-1150 rounds/min)... the latter obviously not participating in dropping full-mags... that'd be unnecessary (albeit fun! :smallwink:). You do get more specialised groups that will carry larger calibre MGs that a single bloke can carry, but they are unusual. A 50cal isn't typically carried out into the field because of the need for two blokes to carry it (usually not enough bang for buck) and the fact that they normally use tripods to fire from. So really, in single man-portable weapons you probably top out at the 7.62mm MGs. That said, those LMGs and MGs are great at area denial as they actually do have an area of effect (the beaten zone (http://en.wikipedia.org/wiki/Field_of_fire_(weaponry))) that you use when shooting.

[jaybird]

There are plenty of extremely effective man-portable automatic weapons. A SAW for example, easily man-portable, and it can be very effective if you're standing up when that thing shots you might have a problem, a 240 is even more effective and still man portable. A 50 cal, isn't quite man portable (requiring two mans to carry it) but it can still be fairly man portable. Cones are pretty effective as firing methods for automatic weapons and really you can't go into those areas because they are fatal, they're just known, basically it's battlefield control.

Not...quite. Even SAWs are significantly heavier than assault rifles. The USMC is switching to the IAR, effectively an assault rifle with a heavier barrel, because of weight and accuracy problems with the M249. A traditional LMG suppresses with the psychological effect of hearing sustained automatic fire, which can be overcome by experienced and motivated troops, because the era of charges into entrenched positions ended a long time ago for modern armies.

Now, if it takes practically a linebacker to hump the M249 effectively, how many boots do you think it takes to bring a Browning into action?

[AMFV]

Not...quite. Even SAWs are significantly heavier than assault rifles. The USMC is switching to the IAR, effectively an assault rifle with a heavier barrel, because of weight and accuracy problems with the M249. A traditional LMG suppresses with the psychological effect of hearing sustained automatic fire, which can be overcome by experienced and motivated troops, because the era of charges into entrenched positions ended a long time ago for modern armies.

Now, if it takes practically a linebacker to hump the M249 effectively, how many boots do you think it takes to bring a Browning into action?

Two.

I've humped with those weapons, they are most certainly man portable. I'm not built like a linebacker, and I've seen them humped by folks that are much much smaller than I am. So it's certainly possible. The M249 isn't as terribly heavy as you make it out to be, it only becomes heavy when you also have 45 lbs of body armor as well, which is part of the problem. Besides which suppressive fire is far more than a psychological effect, with a tripod you can certainly hit point targets with a 240 or 249. In fact I was much better at hitting with those weapons, and tracers than I was with a standard rifle. It just takes a lot of ammo to do anything.

The era of suppressive fire is far from over as the 250,000 bullets fired to one insurgent killed statistic shows. The majority of all ammunition is expended this way. Because in RL as in D&D BFC is more important that simply being able to kill your enemy.

[Mr. Mask]

Heck, John Barcelona carried a machine gun himself, and shot people with it while standing. Just like Rambo.

[Slylizard]

Not...quite. Even SAWs are significantly heavier than assault rifles. The USMC is switching to the IAR, effectively an assault rifle with a heavier barrel, because of weight and accuracy problems with the M249. A traditional LMG suppresses with the psychological effect of hearing sustained automatic fire, which can be overcome by experienced and motivated troops, because the era of charges into entrenched positions ended a long time ago for modern armies.

Now, if it takes practically a linebacker to hump the M249 effectively, how many boots do you think it takes to bring a Browning into action?

Yeah, when you're talking about lugging around a 10+kg (about 7-8 in Oz) weapon all day it can become painful. Still portable though :P Brownings and the like are generally right out for slogging through the field, they're typically mounted on vehicles or have a tripod (so static defence somewhere).

Spot on with the psychological thing though... but that's what suppressive fire is. It's not effective fire (as in putting rounds into bodies) it's simple using sound/threat to force people to stay down. The more experienced/motivated the target is though, the less likely that suppressive fire is to work.

[jaybird]

Two.

I've humped with those weapons, they are most certainly man portable. I'm not built like a linebacker, and I've seen them humped by folks that are much much smaller than I am. So it's certainly possible. The M249 isn't as terribly heavy as you make it out to be, it only becomes heavy when you also have 45 lbs of body armor as well, which is part of the problem. Besides which suppressive fire is far more than a psychological effect, with a tripod you can certainly hit point targets with a 240 or 249. In fact I was much better at hitting with those weapons, and tracers than I was with a standard rifle. It just takes a lot of ammo to do anything.

The era of suppressive fire is far from over as the 250,000 bullets fired to one insurgent killed statistic shows. The majority of all ammunition is expended this way. Because in RL as in D&D BFC is more important that simply being able to kill your enemy.

Sure - the problem is that every pound counts on the heavy modern day load. That tripod? More weight to carry. The amount of ammo expended? More weight to carry. They're man portable by themselves, but the whole package is frighteningly hefty. When infantry are on long foot patrols, that takes a serious toll on combat effectiveness.

The era of suppressive fire is not over, but the weight associated with traditional suppressive fire has become a problem.

Also, "and really you can't go into those areas because they are fatal" from the post I quoted was what I was trying to respond to, making the point that a cone of fire is not an area where anyone sticking his head out instantly dies.

[Knaight]

Back onto simulation: I just looked up the rules in Nemesis.

The core rules: You roll a pool of 10 sided dice, and look for matched numbers. These are sets, with a width equal to the number of dice in the set and a height equal to the number that was matched. Dice rolled range from 2-10 for a given action, usually being somewhere around 5-7 for something a character is good at.

Nemesis then implements two autofire options. One of them is Spray, the other is Suppressive Fire.

Spray: Automatic weapons have a spray number. Add this to the Coordination+Firearms skill, and roll all the dice. Every set found is a hit, and you use one bullet per die in the pool. The absolute best case scenario here is landing half of your shots, which is extremely unlikely.

Suppression Fire: Fire over an area. Roll 2 dice, plus Spray dice, and look for sets. Everyone in the area who isn't behind cover rolls 1 die, and if it matches any of your sets they get shot. You aren't all that likely to hit with this unless the area is pretty packed, but sticking your head out under suppression fire isn't the best idea. It also requires the equivalent of a morale check from the characters, unless they are sufficiently hardened to violence.

A fully automatic weapon gets 5 spray dice, which is about a 60% chance of a match before adding in skill of the character or the 2 for suppression fire. A SMG only gets 3, which is closer to a 30% chance.

[Mr Beer]

Is that, twenty rounds per round, or twenty rounds per character?

In this hypothetical 4 vs. 15 combat, that would be 20 rounds each per round, so 380 rolls. Let's hope this doesn't go on for more than a couple of rounds.

Twenty rounds isn't a lot, a standard military rifle can put out 10 rounds per second and most systems have combat rounds that last longer than a second.

There are numerous heavy weapons that fire faster than that, and while I think it's unlikely you'd often need to model a minigun dual, at up to 100 rounds per second, it would be a time consuming battle to play play.

Aside from the length of time it would take to play out, one bullet = one attack doesn't really make sense...if you are attacking multiple targets, you neccessarily have automatic misses. Suppressive fire isn't intended to hit anyone. Recoil is a thing, as is the richness of target environment.

Pratically speaking, you need a different approach than one bullet per roll, just to get the combat done in any reasonably time frame. And if you're addressing some of the more obvious factors I've mentioned above, you're already committed to a less simplistic modelling system anyway.

[Mr. Mask]

Yeah, suppressive fire isn't really an attack. You could try and put 3 rounds one one guy then three rounds on the next, depending on the length of combat rounds.

With suppressive fire, I don't think you'd even roll for it. Some kind of initiative roll to see who shoots first, then everyone in the effective area of your suppressive fire would have to make some defensive rolls. Morale rolls to avoid ducking for cover just from the sound and sight of the gun firing, genuine cover rolls if you're sweeping or focusing the fire over them, that kind of thing. Skill of the gunner plays a part in that latter example though, so you'd need to factor that in.

Talked this over a while, thinking of just it. While shots past the fifth round are of questionable accuracy you can sill drag the rifle back onto a target during full auto, so they aren't useless. The Vulcan cannon has also had my consideration, as it fires 100 rounds per second--getting more accurate after so many rounds (I've never heard how many) and stabilizing into an highly accurate, extremely rapid weapon. Rolling one to six hundred times a round doesn't pan out.

Rolling once to see how many of your remaining shots hit after you reach your weapon's minimum accuracy is my line of thinking. I could probably do it with the standard kind of roll I'm using, and get the math formula to a single case of division or adding (whichever the player prefers).

I've read a number of your posts on this forum, and I'm happy to be able to discuss this with you. It's a nice break from the RPG I've been working on, which is all melee.

[Sith_Happens]

I remember seeing a suppressive fire houserule for d20 where you make no attacks initially but threaten a chosen area until your next turn. Add clauses to that such that
Attacking from the threatened area provokes
Each square exited provokes rather than one provocation for the whole movement
You have no limit on the number of AoO's per round you can make this way
Tumble or its equivalent is ineffective unless you have Evasion
and you have an extremely simple mechanic that produces the desired effect.

[AMFV]

Yeah, suppressive fire isn't really an attack. You could try and put 3 rounds one one guy then three rounds on the next, depending on the length of combat rounds.

With suppressive fire, I don't think you'd even roll for it. Some kind of initiative roll to see who shoots first, then everyone in the effective area of your suppressive fire would have to make some defensive rolls. Morale rolls to avoid ducking for cover just from the sound and sight of the gun firing, genuine cover rolls if you're sweeping or focusing the fire over them, that kind of thing. Skill of the gunner plays a part in that latter example though, so you'd need to factor that in.

Talked this over a while, thinking of just it. While shots past the fifth round are of questionable accuracy you can sill drag the rifle back onto a target during full auto, so they aren't useless. The Vulcan cannon has also had my consideration, as it fires 100 rounds per second--getting more accurate after so many rounds (I've never heard how many) and stabilizing into an highly accurate, extremely rapid weapon. Rolling one to six hundred times a round doesn't pan out.

Rolling once to see how many of your remaining shots hit after you reach your weapon's minimum accuracy is my line of thinking. I could probably do it with the standard kind of roll I'm using, and get the math formula to a single case of division or adding (whichever the player prefers).

I've read a number of your posts on this forum, and I'm happy to be able to discuss this with you. It's a nice break from the RPG I've been working on, which is all melee.

Well you're never going to be able to fire a Vulcan sans tripod, that's just going to be awful if you attempt it. Most weapons are accurate past the third round if they are fixed to a point. Other than it looks very workable, it is possible to keep a weapon on target firing full auto, just very very difficult. Now suppressive fire isn't intended to kill somebody, but if you stand up and walk towards a machine gun that's laying down an arc of fire, you're probably going to have a bad time even if they're not directly aiming at you.

[Mr. Mask]

With the Vulcan Cannon, I was thinking of attack helicopters being the main area it would pop up. It would be interesting to see someone try to fire that thing without a tripod.

I agree with your other points. Hopefully, I have something satisfactory for putting excess bullets on a target.

There are a number of kinds of suppression; that or the word is too generic. Kids who duck just from the sound of some of the machine guns when they present no threat; Blind fire making enemies duck more as a factor of intimidation than danger; An Mk19 grenade launcher putting so much shrapnel in an area that you can't safely come out of cover, or the same thing from wild bullets; You can lay fire on a window, edge of a building, over trenches, wherever, so that attempting to pop out is likely to occur in extreme cranial acupuncture; And nothing like the good old, "Strafing fire on anything that moves."

That's my current break down of suppression... I miss anything? I'd like to give this thorough work and make it into my next RPG project, but until I get the first one done it's unfortunately more of a hobby.

[Slylizard]

With the Vulcan Cannon, I was thinking of attack helicopters being the main area it would pop up. It would be interesting to see someone try to fire that thing without a tripod.

I agree with your other points. Hopefully, I have something satisfactory for putting excess bullets on a target.

There are a number of kinds of suppression; that or the word is too generic. Kids who duck just from the sound of some of the machine guns when they present no threat; Blind fire making enemies duck more as a factor of intimidation than danger; An Mk19 grenade launcher putting so much shrapnel in an area that you can't safely come out of cover, or the same thing from wild bullets; You can lay fire on a window, edge of a building, over trenches, wherever, so that attempting to pop out is likely to occur in extreme cranial acupuncture; And nothing like the good old, "Strafing fire on anything that moves."

That's my current break down of suppression... I miss anything? I'd like to give this thorough work and make it into my next RPG project, but until I get the first one done it's unfortunately more of a hobby.

Suppressive fire is generic, there's a lot of ways to pull it off. Really it is any fire that causes an enemy to keep their heads down "fire that degrades the performance of an enemy force below the level needed to fulfill their mission".

Everything you have described above is suppressive fire. What you're trying to do is simply shoot at an enemy (that you likely can't hit) with the intention of making the risk of sticking their heads out and shooting back (or moving) to large to be worth it.

Mechanically, I'd say your best bet is to threaten an area (size of that area depending on the weapon employed), and giving the enemy a combination of some sort of willpower save to move/shoot back (overcoming the threat), and reflex save (to avoid being hit by that threat) before they get to take an action within that area.

[Mr. Mask]

I agree with what you say.

The last point of how to handle it mechanically, what you describe is the same line I've been thinking along.

Set an area of fire where anyone in it ducks, or is recruited into the Swiss' Cheese corps. You'd want it that the narrower and more focused the suppressing fire was, the more likely they are to get lead poisoning if they stuck their heads out. Differentiating between wild bullets/shrapnel and intentional fire also seems desirable.

People outside the danger zone should have to make willpower saves. You need to have the right factors in for these saves... experienced soldiers with solid cover far out of the enemy's effective range are much less likely to duck and stop firing.

It's tempting to make this a project...

[Rabidmuskrat]

Consider this. You are fighting something the size of a house. You have a minigun capable of firing 500 rounds per minute. How do you model this? Area/suppressive fire thing is a pretty terrible mechanic, I am pretty sure anyone with moderate skill will be able to put most if not all of his shots on target (a minigun has a gyroscopic effect), dealing potentially devastating damage.

Now that I think of it, unless the target has armour capable of completely resisting all damage from a single shot something like 90% of the time, it is pretty safe to assume that it is nothing but a bloody mess after 6 seconds of firing. That seems like a pretty good model. Does it have cover to hide behind? If no, does it have armour that can nullify the damage? If no again, its just dead.

[Mr Beer]

One my favourite combats was 2 PCs armed with Soviet WWII PPsh sub-machines vs. a T-Rex, modelled in GURPS 3rd Ed. There was a 3rd PC but he had Fear Of Reptiles and I felt a bull T-Rex imposed an additional penalty on his Fright check.

The PCs won quite easily, their skill + the weapons Acc allowed them to spray it's head with bullets. While the skull resisted easy penetration, they were doing enough damage to make it difficult for the poor beast to attack and within 3 or 4 rounds it died :(

[Mr. Mask]

Muskrat: You can fire on targets individually, or suppress an area. Something the size of a house would have low defence against being shot; easy to hit.

The best armour is not getting shot. Second best is a reinforced concrete bunker designed for surviving nuclear bombardment. Trenches, armour (tanks, APCs), and infantry body armour are also helpful.

Survivability depends on how many bullets hit, where they hit, and the involved gun's calibre and ammo type in use.

[Berenger]

The sound of one of the German machine guns (...which one WAS it!?) had a reputation for making green soldiers duck, just from the sound of it going off. If the gun was firing in your general direction, even when the shots weren't going to hit you (this is very hard to judge in combat), you would find it very difficult to not duck for cover.

I guess this would be the Universal-Maschinengewehr Modell 42, aka "MG 42", "Hitlersäge" (Hitler Saw), "Hitlersense" (Hitler Scythe), "Knochensäge" (Bone Saw) and "Singende Sense" (Singing Scythe).

[BWR]

This is another topic that pops up from time to time.
Dragonstar, FFG's D&D in space game, treats it like this:
Burst fire uses normal attack bonus on the first shot, and for each 5 points your attack roll exceeds the target's AC another shot hits (feats allow you to reduce the penalty). Only the first shot in a burst is critable.
You can fire a burst with each of your normal attacks. People with a high attack bonus and several attacks can deal ****loads of damage to poor, low AC targets. Having a low AC in combat with autmatic weapons almost guarentees death within a round or two.

Full auto fires a cone the length of the weapon's range increment. You make one attack roll at -4 penalty against all targets in the area, which cannot crit. Anyone struck is allowed a Reflex save (DC = to number of shots fired, which is 5 bursts, meaning usually 15 shots). If failed, the taget takes normal damage and the next target's save DC is one easier than the last. This is a one round action that leaves you flat-footed while performing it (meaning anyone moving into the AoE before the beginning of your next turn is subject to an attack). Once a number of targets equal to the number of shots fired have been targeted (regardless of whether the attack hit or did damage), you have spent all your shots.

[hymer]

CP2020 makes auto-fire almost the best action you can take: you get a bonus for every 10 rounds, and deal 1 hit for every point over the DC you roll.

I don't have my CP2020 rulebook handy, so this will be by memory: Yes, against multiple foes in close combat, autofire is excellent (since you can decide to attack any opponent you can see with any number of shots - and you're likely to be able to fire over 20). But you get a vast penalty when going out to a certain distance, and you can't aim autofire at specific body parts. In CP2020, hitting someone in the head is 10% if you fire without aiming, and it's the surest way to down an opponent. You only need to get 4 points of damage through to their skull, and they're dead (because all damage to the head is doubled, and eight points takes an extremity out).

Edit: This is why assault rifles are so good in CP2020, btw. If only they could be concealed in a pocket! You get good range so you can shoot people in the face from a distance, and if you're in streetfighting turning a corner, you can fill almost any number of people full of lead. Just be careful you don't run out of ammo.

[Cespenar]

I don't know the exact mechanics behind it, but Fallout 1-2 did it pretty good, in my opinion.

As in, when you autofire, there will be collateral damage.

[hymer]

I don't know the exact mechanics behind it, but Fallout 1-2 did it pretty good, in my opinion.

As in, when you autofire, there will be collateral damage.

Not if you stand adjacent to the target. Then you're likely to get a rather gruesome and lovely death animation instead. :smallbiggrin:

[Cespenar]

Not if you stand adjacent to the target. Then you're likely to get a rather gruesome and lovely death animation instead. :smallbiggrin:

Yeah, nothing like an automatic shotgun burst at point blank range to denounce one's belief in overkill.

[Mr. Mask]

Berenger: Not one, but SIX names and I still didn't remember it? This must be your fault, somehow!

[Berenger]

Mea culpa.

[Mr. Mask]

Te absolvo.

[Vknight]

Eclipse Phase and its rules on the matter

Full Auto: Apply one of these benefits
+30% to Hit: You are shooting at everything
+3d10 damage: Focus fire on the target

Nice and simple in a percentile system

[Isamu Dyson]

I like how GURPS handles automatic fire: you score extra hits per Margin of Success on your attack roll equal to the gun's Recoil stat. You typically end up missing most of your shots with a long stream of bullets, but that's realistic, and there are ways to counteract this (action-movie hero level Skill, for instance).

[Hida Reju]

If I remember right Dark Heresy let you get extra hits for burst fire and auto fire by doing better on your to hit roll.

If you had a Ballistic skill of 40 and it was modded up to 55 after all modifiers and rolled a 35, you would get up to 4 extra shots of damage using auto fire. The exact limit on how many hits you could get was based on the weapon and your skill in using it.

They also did a suppressive fire option that targeted an area and gave a chance for every target in the area to take a multiple hits.

It was not perfect but it got the job done.

[Rhynn]

All right, so, Twilight 2013 automatic fire.

Tasks in TW2013 are resolved by rolling multiple d20s against (equal or under) a target number set by your attributes (the human range is 2-12 and above, with 7 as the average; 12+ requires training during your lifepath and generally signifies world-class ability). For non-skill ability checks, you roll 2d20 and use the better (lower) result. For skill checks, skill ratings determine how many dice you use: novices get 1d20, professionals get 3d20L (use lowest), and the best, at legendary, get 6d20L. If you are completely unskilled or specially disadvantaged, you use 2d20 and use the worse (higher) result. If you get a success on the best die, you take the margin (difference between roll and target number; this can be 0), which determines how well you did. If more than one die came out under the target number, each extra die adds +2 to the MoS (Margin of Success). Penalties reduce the target number, bonuses increase it.

So, with a respectable Coordination of 10 (scores of 10+ in the right attributes are good enough you e.g. qualify for Special Ops training) and no skill with Handguns, you'd have a base 25% chance (2d20H, use the higher/worse result) of hitting something you're shooting at. With Novice skill, you'd have a 50% chance (1d20). With Competent skill, you'd have a 75% chance to hit something, and 87.5% at Professional... under ideal conditions and up to 7 meter range. At 25 meters (-1), your odds would go down to 20.25%, 45%, 69.75%, and 83.3625% - that's assuming a handgun with good range (the CQB range band is "optimal" for it) and no telescopic sights.

Side-note on range bands: the game tracks ranges loosely, but with definitions that make it possible to track them closer. The bands and ranges are as follows:
Personal (in close combat)
Gunfighting (up to 7 m)
CQB (7-25 m)
Tight (25-100 m)
Medium (100-200 m)
Open (200-400 m)
Sniping (400-800 m)
Extreme (800-1600 m)

They work in two ways: first, seeing or shooting out to these ranges with the naked eye is hard (-1 at CQB, doubles at every band out from there, to -32 at Extreme). Telescopic sights reduce your penalty by one step per point of rating; e.g. a rating 3 telescopic sight treats Extreme range as Medium.

Secondly, all firearms have range expressed as X/Y, where X is the "optimum" range and Y is the "maximum" range. Shooting at targets closer than your optimum range is slower (you have to turn/move your weapon more; a handgun is much more convenient and quicker to aim at close ranges than a rifle, when fractions of a second count), and shooting at targets beyond your maximum range gives a -3 penalty per band outside the maximum range. The range for most handguns, for instance, is Gunfighting/CQB (it's harder to get a bead on someone who's close enough to punch you than someone who's 10-20 feet away).

Briefly, TW2013 combats are of ambiguous length, divided into "exchanges of fire" (combat rounds; these are rarely more than 10 seconds long each, but there's no set length); exchanges can follow each other, or be broken up by pauses (which usually last less than a minute). Characters can take Tactical Actions (shooting, moving, exchanging a mag, etc.) during exchanges, and Operational Actions (removing gear/clothes, setting an ambush, administering first aid, reloading all weapons). Exchanges are divided into "ticks"; after initiative is determined, a count-down starts from the highest initiative, and each action eats up a set number of ticks. (There's two rules options here: either your action resolves immediately and you act again at a lowered count, or your action is resolved on that lowered count. The latter is more realistic, and means e.g. that a hasty but lucky shot can drop an opponent drawing a careful bead on you to blow your head off.)

The shooting actions are Hip Shot, Snap Shot, and Aimed Shot. They each have a different cost dependent on your weapon (handguns are faster to move and aim than rifles or support weapons). For instance, a Glock 17 has a speed of 1/2/4 (ticks costs for Hip/Snap/Aimed Shots), while a generic assault rifle has a speed of 3/5/7. If you're shooting at something closer than your weapon's optimum range, you add +1 per range band to the action cost.

Burst Fire
Weapons have a ROF, and some have a Burst ROF (expressed as B#, for instance B3 or B6). When firing a burt, you get a bonus to hit equal to the number of additional rounds (e.g. +2 for a three-round burst, +5 for six rounds). If the attack hits, you roll 1d6 for every extre round fired; on a 1, that round hits the same location as the first shot, and on a 2 or 3 it hits a random location. 4-6 are misses. (So if you hit with a burst, an average of half the bullets will miss - but there's going to be huge variation with small bursts, and you might pretty much blow someone apart with lucky rolls.)

Note: There's a legitimate complaint to be made here that range and other considerations don't affect the likelihood of the other rounds hitting; since range amplifies deviation, you should have a better chance of hitting with extra bullets at e.g. Gunfighting range than at e.g. Open range... but that would probably get stupidly complicated to model.

Recoil
Recoil is very important to burst fire. Each gun has a Recoil value. For single shots, you compare Recoil to the shooter's Muscle (2 to 12+, with 7 the average and 9+ good enough for Special Ops training).

For comparisons, .22 target pistols have Recoil 3, a .40 S&W pistol has Recoil 9, a .454 Casull revolver has Recoil 16, a generic 5.56mmN assault rifle has Recil 4, a 7.62x51mm battle rifle has Recoil 9, a .30-06 bolt-action rifle has Recoil 11, a .50 BMG anti-materiel rifle has Recoil 24, a 12-gauge pump-action shotgun has Recoil 19, and so on.

If Recoil exceeds your Muscle, if your next action is a Hip Shot or Snap Shot, it takes a penalty equal to the difference. So if you have Muscle 8 and you fire two single shots in a row with your battle rifle, the second one is at -1. If you have Muscle 8 and fire a 12-gauge shotgun, your next action would take a -10 penalty (basically impossible). As an aside, holding a handgun in both hands increases your effective Muscle by +2. So this Muscle 8 soldier could fire a .40 S&W pistol again and again, over and over, with no recoil penalties - he's strong enough to compensate between shots without slowing down. (Kneeling, lying down, etc. also helps compensate for recoil, as do bipods, tripods, and vehicle mounts.)

Note: This might be abuseable, in theory - perform an irrelevant 1-tick action in between - it's up to the GM to police rules abuses, obviously.

For burst fire, Recoil is increased by the number of additional bullets (so firing a B4 burst with your Recoil 9 battle rifle makes the effective Recoil 12), and the recoil penalty applies to the attack. So our Muscle 8 soldier firing that B4 burst with his battle rifle takes a -4 to hit, actually outweighing the +3 from the extra bullets.

There's no "full auto" action, because that's generally a horrible idea. However, there are rules for characters who don't understand the principle of short, controlled bursts and just hold the trigger down: they use twice the number of ammunition per burst (the extra bullets are "wasted" and can never hit the target), and get a -2 to hit.

Note: There's no rules for hitting multiple things or things you weren't shooting at, but a GM could certainly adjudicate this - for instance, if you're shooting down a hallway at a tight group 20 feet away, maybe the bullets that miss the first guy have a 3/6 chance to hit the next guy, and so on.

Each character in TW2013 has a Coolness Under Fire (CUF) attribute. The GM assigns Threats to characters (representing them with tokens - poker chips and empty casings are mentioned as good choices), for things like being in combat, being attacked, being attacked with lethal force (that's up to 3, which might be enough to scare a nervous civilian), burst fire, explosives, incendiary weapons, obviously insane enemies, being ambushed, fighting in the dark, being outnumbered, being unable to see your enemy, being hurt, seeing your friends go down, etc.

Certain actions and conditions reduce Threat, including taking down an opponent, taking pain killers, being part of a solid team that has trained and worked together (there's Team rules) having someone scream at you reassuringly (the "You Wanna Live Forever?" action, which uses the Command skill), and firing a wild burst ("Panic Fire" - it can't hit anything).

If your Threat exceeds your CUF, you take a penalty on actions equal to the difference. If Threat exceeds CUF by 5+, you are broken and can only flee, perform first aid on yourself, communicate (yell for help), or curl up and cry, and if the enemy calls for you to surrender (usually an opposed social skill check), you will.

Suppressive Fire
Suppressive fire is a snap shot action at an area, with a width in meters up to one-half the number of bullets fired (i.e. 50 cm for a single shot, 3 meters for a B6 burst, etc.). Everyone in the area has their Threat increased: by 1 if 1-5 shots were fired, by 2 for 5+ shots. Tracer rounds or explosive rounds increase threat by another 1 (since you can see the shots).

Anyone who exposes themselves to the suppressive fire (i.e. pops out of cover to take a shot or move around) has their Threat increased (for the rest of the exchange). In addition, if they expose themselves, the character laying down suppressive fire gets another (free, 0-tick) attack on them, with the same ROF as the first attack.

Note: It's not explicitly spelled out, but one assumes that laying down suppressing fire means you don't get to do anything else that exchange.

Johnny Marine is fighting two bandits in the forests of post-apocalyptic Poland. They're lying behind a bank of earth, and Johnny is lying down behind a tree. The bandits aren't trained soldiers, and they're pretty new to this "robbing and killing" (Green NPCs, CUF 3).

Johnny has an M4A1 carbine (ROF Single/B5, Speed 3/4/6, Recoil 5), CUF 8, and Muscle 9. The bandits surprised him and fired some single shots with their AK-47s but missed, and he threw himself down, sighted them, and takes aim to fire a burst at them to suppress them (B5 for a 2.5 m wide area, more than enough for the two bandits laying near each other). The bandits go prone to hide behind the bank (2 ticks, resolving before Johnny's shot), and are now in cover from him.

Johnny has Threat 5 (combat, attacked, lethal force, ambush, outnumbered), and the adrenaline is pumping - he's got no penalties.

The bandits have Threat 4 (combat, attacked, lethal force, burst fire). Unfortunately for them, Johnny has tracers in his mag, and if they expose themselves (e.g. pop up to a kneeling position to take a shot at him), their Threat will go up to 6, inflicting a -3 penalty to their actions. That means they might not want to do it at all, and spend the entire exchange in cover - especially since popping up for a shot would mean Johnny getting to fire a burst at them (and he's probably got a very good chance to hit).

If Johnny were to throw a hand grenade (1 Threat) and hit both bandits with fragments (slight injury or worse), they'd be at Threat 8+ and would have to flee or surrender.

Basically, with a well-stabilized or low-recoil weapon, burst fire can be very useful in cutting enemies up, and every team should have someone laying down suppressive fire every exchange, if feasible (an FN MAG/M240 has a ROF of B11, and can suppress 5.5 meters and cut apart someone who sticks his head out). The average person isn't going to do too good firing an AK-47 or a 7.62x51mm battle rifle on automatic, though - exchanging accuracy for the chance to score multiple hits.

Also, cover is absolutely essential, not least because kneeling makes you harder to hit (-1), but because any part of your body that would be behind the cover is protected by the cover, and any bullet that hits a covered location (hit locations are determined randomly) will have to penetrate the cover first. A sandbag will generally offer great protection from rifle rounds (especially at longer ranges), and a solid stone, concrete, or cinderblock wall will be even better. Most of the time, combatants would be entirely behind cover, popping out to take a shot now and then. (Provided they're not being suppressed, anyway.)

The rules are far from a perfect simulation of reality, but the divergences are obviously decisions; and they strike the best balance I've ever seen between playability and realism. The system is already quite heavy, although IMO very playable, and additional realism would weigh it down even more. The resulting effects on gameplay, in any case, are sufficiently realistic.