Balancing Guns & Swords

[Sir Sanguine]

Hi forums!

Okay. I'm trying to write a RPG system and setting. The setting is basically a collision between the real world (as it is right now) and a "fantasy world" which contains every sort of monster and concept humans have ever dreamed up. The fantasy world has magic aplenty, in addition to being stereotypically medieval- people fight with swords and halberds and armor and such. Big portals are opening between that world and this one.

But anyway, the party in this setting are from the modern world. So it stands to reason they would bring along some guns before they go fight the native hydras or whatnot. And that's kind of cool- I like the mythical beast vs. really big guns thing. Buuut, I also want the players to be able to act as more traditional fantasy heroes who have armor and swords and things. I was envisioning a mix of gun guys and sword guys within the party.

Problem: guns are (obviously) better than swords. Quite a bunch of the swords are going to be magical, but not all of them can be. So in a fight against, say, a bunch of orcs, I want everyone to be able to contribute.

Does anyone have any suggestions for balancing ordinary melee with guns?

[Kiren]

All depends on the era and type of firearm, their is a deadliest warrior episode pirate v.s. the knight which shows firearms v.s. armor and guns.

Guns of the pirate era are slow to reload, so pirates would carry multiple pistols because reloading during battle would likely kill you. I think some carried 5.

Guns of the pirate era are inaccurate and are dangerous *I'm going from memory but I think they can backfire*. However guns can pierce armor when arrows may not, it is also harder to dodge a bullet then it is to dodge a arrow *although maybe if your lucky the bullet will veer off*

Also, the firearms cannot get wet, the gunpowder cannot ignite wet.

Overall I suggest watching the deadliest warrior Pirate v.s. Knight episode, they got plenty of useful information and a deathmatch between the two.

[Slayn82]

Have you given a look at this?
http://69.8.198.251/default.asp?x=d20/article/msrd

It has the rules for modern weapons in the D20 sistem. They are not "realistic", so that an AK 47 will not do 60 shots per round, but works. The main advantage is that automatic weapons have feats that allow to spray an area, to deal damage in anyone who fails an reflex save ( to find cover, i guess). But they consume a large amount of bullets to do so.

Also, if none of the PCs could make gunpowder, they would be limited to the amount of ammo they originally had. If someone could ( and its not that hard), then there is the fact that they will need Sulfur (somewhat expensive in a historically acurate medieval scenario, but in fantasy could be plenty around), sodium nitrate (guano is your best bet), and vegetal coal (better for the gunpowder).

Repairing modern weapons with magic is easy, but reproducing then from scratch could be a little dificult, because industrial precision is a pain, and most mages would not have a good compreension of such standards. Often a 0.15 mm tolerance can determine if two parts slide freely or jam. So complex weapons, like most semiautomatics or automatics, are ruled out in most cases for reproducing, unless someone has good knowledge of mechanics involved and cares to get a precision instrument around. Shotguns, revolvers and simple pistols could be reproduced ok, in most cases, and you can balance the precision if you think the char could not have made a good work. Deffective fabrication could also justify a redution in the damage of the weapon.

[Kiren]

A important bit of info pertaining to the production of firearms, up until the industrial revolution and the assembly line/interchangeable parts, firearms could only be constructed by skilled craftsmen, and not mass productive.

[LurkerInPlayground]

Simple. A lot of monsters are going to be resilient. So even if they're mortally wounded, they just keep on going with blind aggression, unless you have a gun big enough to knock them on their ass or blow out a large bore hole out around their apricot.

Of course, you get the same problem with spears, I suppose, which is why they had to invent boar spears. Basically, the cross-guard on a boar spear stopped the boar from charging up the spear and goring you anyway.

Arguably, maybe guns are just much harder to enchant than melee weapons. Their increased complexity (i.e. moving parts) means that each individual piece has to be custom enchanted separately and enchanting weapons are not an exact science. In mechanical terms, this just means guns with lower enhancement bonuses. You're far more likely to find a +5 long sword than a +3 .45 magnum. It's a longstanding tradition to enchant blades. Guns, not so much.

[Kiren]

Simple. A lot of monsters are going to be resilient. So even if they're mortally wounded, they just keep on going with blind aggression, unless you have a gun big enough to knock them on their ass or blow out a large bore hole out around their apricot.

Of course, you get the same problem with spears, I suppose, which is why they had to invent boar spears. Basically, the cross-guard on a boar spear stopped the boar from charging up the spear and goring you anyway.

Arguably, maybe guns are just much harder to enchant than melee weapons. Their increased complexity (i.e. moving parts) means that each individual piece has to be custom enchanted separately and enchanting weapons are not an exact science. In mechanical terms, this just means guns with lower enhancement bonuses. You're far more likely to find a +5 long sword than a +3 9mm handgun. It's a longstanding tradition to enchant blades. Guns, not so much.

The bullets would be enchanted, that or the black powder *a little less realistic but hey its magic*.

[LurkerInPlayground]

The bullets would be enchanted, that or the powder.

Huh?

Not necessarily. A more accurate gun might be able to dissipate excess heat more rapidly and have a chamber which causes gases released from the powder to expand more evenly and consistently from shot-to-shot. The firing pin might be reinforced so that it is harder and less likely to lose durability over time (which causes inconsistent strking of the primer). Basically, any kind of customized technique to lower any undesired entropy in the gun would be desirable (i.e. increase efficiency).

You can also reduce bulk or the cumbersome nature of a long arm by selectively reducing the weight of certain components or attachments of the gun while still retaining durability. The same principle can be applied to enhance overall balance. A rather neat application of this trick would be to help lighten the trigger pull, making a more precise weapon.

Another example would be a magically enhanced red-dot sight. Maybe the lens is enchanted to project an image of the future in one-or-two seconds, which allows the shooter to better anticipate his shot. Maybe it magically highlights aggressors for quick identification.

The ammunition could be enchanted seperately, but even that has several components: cartridge, bullet, powder and primer.

We should also mention that low-grade black powder gave a lot of smoke and tended to foul up guns. So enchantments that make the powder burn cleaner might be a helpful workaround for low-grade powder.

Melee weapons are, for the most part, relatively simple. You don't have as many technologies or problems involved.

Maybe the guys who enchant weapons don't have the faintest idea what mercury fulminate is.

[Human Paragon 3]

What kinds of guns are you going to use? I had to homebrew a musket once because the ones in the book were too terrible to compete with regular bow and arrows.

Musket Stats:
martial weapon
Damage: 3d8. Crtical x3. full round action to load, standard action to fire. "rapid reload" feat lets you load as a move acation.

This puts them on a par with a bow and rapid shot. I would also allow a variant on manyshot (load multiple bullets).

[lightningcat]

In my campaign, a spellpunk renaissance style setting, I was using more modern firearms (from about to the Victorian/Wild West era). I balanced firearms with standard weapons with the price of ammunition. The premise was even with gunpowder being rare and hard to make, firearms would continue to develop if only to make the limited supply of gunpowder.

That might not work in your case. Guns are inevitably more dangerous then melee weapons. This of course follows real world history; the range, penetrating power, and level of skill needed to use effectively are simply better. Once you get to the modern era you also have the benefits of mass production and cheap gunpowder.

The benefit of small melee weapons (knives, clubs, etc) are concealment and lack of sound when used, as well as lack of restrictions on ownership.
You might deem that firearms cannot be enhanced with magic, or that they are less then effective when dealing with supernatural creatures (dragons, fey, magical beasts, and monstrous humanoids), so when fighting those types of creatures you need more primitive methods.

[Human Paragon 3]

Ah, forgot to mention, you can attach a bayonet to the musket, turning it into a short spear.

[Sir Sanguine]

Er, I neglected to mention that travel between the portals is two-way. So reproducing the guns really isn't an issue, although ammo might be if you end up going a long way from base camp. Also, there's going to be a whole lot of people other than the party coming through the portal- military, for one thing.

But thanks for the link. Looking at it, the main distinction between guns and melee is that you can't use melee up close. And, thinking about it, being shot probably does a similar amount of damage to being stabbed with a greatsword. So I guess it's not that damage that's the issue.

I think it's the automatic firing that's the issue. If I've got an AK-47, why can't I just press the trigger and kill, like, all of the Riders of Rohan as they make their glorious charge? That and the fact that armor is useless. Darn.

Maybe some kind of magical solution. Guns could be less effective in the fantasy world, I guess?

EDIT: Liking the "guns and magic don't mix" idea. But we don't want the gun guys to be badass at first level, when it's assault rifles vs. longswords, and then be awful at level 30 when it's Holy Flaming Bane longswords vs. the assault rifles.

[LurkerInPlayground]

Er, I neglected to mention that travel between the portals is two-way. So reproducing the guns really isn't an issue, although ammo might be if you end up going a long way from base camp. Also, there's going to be a whole lot of people other than the party coming through the portal- military, for one thing.

But thanks for the link. Looking at it, the main distinction between guns and melee is that you can't use melee up close. And, thinking about it, being shot probably does a similar amount of damage to being stabbed with a greatsword. So I guess it's not that damage that's the issue.

I think it's the automatic firing that's the issue. If I've got an AK-47, why can't I just press the trigger and kill, like, all of the Riders of Rohan as they make their glorious charge? That and the fact that armor is useless. Darn.

Maybe some kind of magical solution. Guns could be less effective in the fantasy world, I guess?

Not really. A sword is more likely to neatly push its way in. (Although I still wouldn't like getting my limbs hacked off on a chop).

Bullets tend to bounce around inside of the wound before jumping out the other side (as with full-metal jacket rounds). If the bullets fragment instead (as with hollow-point rounds) then you get a situation where the point blossoms out into nasty shards.

So we're talking about wound-trauma here.

Really, if PC's are fighting monsters, it's something less of an issue. A Golem or specific forms of undead probably aren't going to be terribly impressed by bullets one way or the other. (Although a Golem is going to have neat holes punched through it by an endless spray of armor-piercing bullets, it's still up and kicking long enough to crump you.)

The Nazgul, from Lord of the Rings, as portrayed in the movies, were just hollow suits of armor anyway. So there's only so much damage you can do to them in the first place.

So guns might just be *relatively* better. But a monster is still quite tough enough to do some damage on the way out. Likewise, guns are rarely (or never) magical. Maybe the few examples of magical guns are not that great, since they're more like muskets than M4A1's.

[Sir Sanguine]

Yeah, the problem is really orcs and such humanoids. Maybe guns can be good against orcs and swords can be good against big, scary things and that's just the way it is.

[LurkerInPlayground]

Yeah, the problem is really orcs and such humanoids. Maybe guns can be good against orcs and swords can be good against big, scary things and that's just the way it is.

Actually, I'd say guns are better against big scary things too.

But that's beside the point. The natives that have to live with the monsters are more afraid of the monsters than the PC's are. The PC's have technology and the scientific process to back them up. They're just more heroic than knights.

But that isn't to say that fighting monsters, even with a big-honking gun, is entirely risk free. Fighting a chittering hoard of flying insect-men might be easier with guns but it's still hard (they fly and there are a lot of targets because they breed like crazy). They zergling rush you and start clawing you. It's no gun, but if enough of them are tearing and grappling at you at once, then the point is moot.

And creatures like basilisks/gorgons can still petrify you at a glance. And a dragon still remains an armored tank that flies and has a built-in flamethrower.

And the PC's are still fewer in number than clever warriors who might attack them with a knife-in-the-dark or might otherwise shoot them in the back with a poisoned crossbow. Or kill them with traps (step into a hole full of punji stakes). And besides, what makes you assume that humanoid monsters ought to be the biggest threat?

Even then, not all humanoid monsters are about straight-up fights. A Doppleganger can cause problems for the party without ever getting in a fight. Likewise, the PC's might find it distasteful to throw their weight around even if the mob has torches and pitchforks. You don't shoot away all your problems.

Melee weapons can be useful because that's where all the magical swords of legend happen to fall under. They just have magic that's too useful to ignore sometimes, gun-or-no-gun. And a good back-up weapon isn't a bad idea if you run low on supplies and it's too far from the gate to get more ammo. If the locals see that you're petty tyrants, they'll be reluctant to help you with information and supplies.

Besides. Guns break. You have to maintain them. If you need spare parts, you have to bring them or go back home to get them.

[Ouranos]

Look up a game called Rifts.

[lightningcat]

If you don't mind doing a bit or reading there is Hell's Gate and Hell Hath No Fury (Multiverse series) by David Weber. They show a war between a magical world and a science/psionic world. Including a battle between dragons and machine-gun manned pillboxes. They also have the problem of supply lines, as they cross multiple versions of the same world and the gates are not always in the same place.

[Latronis]

Melee weapons are still more effective than guns in the melee weapons 'range'

And unless you actually have the firearm out and ready a knife man can still close the a decent sized gap and stab you before you can get a shot off.

So melee weapons.. oft enchanted and more effective than a bayonet(which would be comparitively less effective than a dagger) still has a place.

The problem then is other ranged weapons

[LurkerInPlayground]

Melee weapons are still more effective than guns in the melee weapons 'range'

Meh.

The thing is that guns don't have to control the fight when it can just skip straight to blowing your ass off. You don't parry a gunshot.

So you get a situation that's closer to "cutting each other down." Assuming the gun doesn't knock the other guy on his ass first. (Generally, this amounts to whether you're using a .45 or a 9mm and whether the other guy is hopped-up on drugs or something.)

Also, if the melee weapons come attached to the sorts of creatures that breed fast enough to zergling rush you, who cares if melee is less than optimal? You fire your gun dry and there's still a hoard leftover to get in your face.

And unless you actually have the firearm out and ready a knife man can still close the a decent sized gap and stab you before you can get a shot off.

True enough.

So melee weapons.. oft enchanted and more effective than a bayonet(which would be comparitively less effective than a dagger) still has a place.

The problem then is other ranged weapons

Crossbows are silenced by definition. Still less-than-optimal, but who cares? Game balance is a bit overrated anyway. You just have to make sure the focus of the game is pulled-off.

[Sir Sanguine]

And besides, what makes you assume that humanoid monsters ought to be the biggest threat?

Not at all! This game is supposed to be more about fighting monsters than humanoids. I just want humanoids to still be *a* threat.

The problem then is other ranged weapons

Yes! That was my other issue. Why use a nonmagical bow ever?

Still less-than-optimal, but who cares? Game balance is a bit overrated anyway. You just have to make sure the focus of the game is pulled-off.

What makes you say that? I don't want the sword-swinging guy to feel like he's useless because the guns are constantly outperforming him. Everyone should get to contribute regardless of what combat style they choose.

I think an important thing is that you can't parry with a gun. So swords would be important for defense, if not able to dish out tons of damage.

[LurkerInPlayground]

What makes you say that? I don't want the sword-swinging guy to feel like he's useless because the guns are constantly outperforming him. Everyone should get to contribute regardless of what combat style they choose.

I think an important thing is that you can't parry with a gun. So swords would be important for defense, if not able to dish out tons of damage.

Maybe you should think less in terms of "specialized shticks" and more in terms of what the PC's ought to adapt to in the setting.

You seem like you're setting up a stranger-in-a-strange land scenario here.

Of course, one of the more obvious solutions is that supplies are very limited. And that the players are not soldiers so much as they are lost or on expedition. (So a player might still have a fireaxe on hand for some reason. Which is still likely a better weapon than what most people in a primitive setting will have.)

[Solaris]

What makes you say that? I don't want the sword-swinging guy to feel like he's useless because the guns are constantly outperforming him. Everyone should get to contribute regardless of what combat style they choose.

The PC sword-wielder is likely to have a high-powered magic sword, so it's really not all that much of a concern whether or not swords can beat firearms. Just don't let the recent arrivals play with magic guns.
Alternatively, simply don't let the advanced gunpowder and percussion caps we use in our modern automatic weapons work in the fantasy world. Just allow black powder weapons to work. They could be more technologically advanced than muskets, but of less power and slower firing rate than our modern weapons. Call a rifle 2d8 damage with a firing rate similar to a bow - way better than a sword, but it's not a machinegun by any stretch and an platoon of archers could still beat a squad of riflemen. Matter of fact, I think you could have a lot of fun with modern-era, mundane troopers adapting to a world whose physics enforce a low-tech approach.

I think an important thing is that you can't parry with a gun. So swords would be important for defense, if not able to dish out tons of damage.

Er... Not so much, and not so much. See, I've actually done fights where a guy came at me with a melee weapon and I used my M4 (training with full contact and simunition - we play hardball in my unit). Starting from across a ten-by-ten room, I still won. It fires on burst, and burst fire > sword. At hand-to-hand range, all you have to do is avoid letting the guy get a hold on you. Don't forget, most melee weapons still operate mostly from about a pace away. At that range, a gun is lethal and can still cross the distance faster than a melee weapon.
Not to mention that an M4 would be better for catching/blocking a blow than a sword would be, considering all the fiddly bits it has. Polymer buttstocks and thin sheet metal magazines won't like it, though. I imagine the black powder weaponry the modern-mundanes who invade would be constructed of tempered steel with wooden furniture intended for roughing it with people who still insist on bringing swords to a gunfight.

[Latronis]

Meh.

The thing is that guns don't have to control the fight when it can just skip straight to blowing your ass off. You don't parry a gunshot.

So you get a situation that's closer to "cutting each other down." Assuming the gun doesn't knock the other guy on his ass first. (Generally, this amounts to whether you're using a .45 or a 9mm and whether the other guy is hopped-up on drugs or something.)

But you have to get the shot off without being disarmed, disabled.. stabbed whatever. You are trying to get a firearm have the business end pointing at your adversary before you fire, your adversary has to stay out of the line of death.

Go for the gun, *stab*

Aim with the gun, *Wrist block, step etc, stab*

Though it is not an everyday situation when we talking about PCs and appropiate challenges that inherent advantage melee has in melee range should be enough to use as a balancing point.

So using a firearm should provoke an attack of oppurtunity. That keeps them deadly within maximum range; But risky to use whenever you are in someone's threatened area. Keeping Melee weapons useful and effective, and letting the firearms really shine at range.

[Rising Phoenix]

This may interest you, by Monte Cook:


http://www.malhavocpress.com/images/Technology.pdf

Cheers,

R.P.

[Demented]

Does a gun trump everything on the contemporary battlefield?

Of course!

Do you find zombies, golems, ghosts, and physiological paragons with immunity to critical hits on the contemporary battlefield?

Hm, no.

A gun is basically a repeating crossbow with better stats and the same disadvantages. It'll suffer far less at a distance, but you'll never get to use your herculean strength modifier... Unless you throw it at someone, of course.

[Swordguy]

Here's the thing: swords never need reloading.

Now, under normal d20 rules, people don't think about the inaccuracy of firearms. Yes, that's right...inaccuracy. Look for a moment with Teh Google at accuracy statistics by FBI, police, and military members for close-range encounters. They're terrible. A 15% hit rate is excellent, even at point-blank ranges. It's a lot harder to hit when you're moving and the other guy is moving. Physics demands this.

If you're 3 feet from the other guy and swinging a sword through the space where he is, he has to vacate his entire body from that space or be struck. If you're 3 feet from the other guy and pointing a pistol at him (say, firing from the hip), you have about a 15-20-degree arc window where the muzzle can move from side to side before you miss him completely. It's not at all like it is in Modern Warfare 2 or something - it's actually very difficult to shoot at and hit a person and anything more than room width. There's plenty of eyewitness accounts from Iraq and the Stan where an insurgent would hose down an entire room with full-auto fire (30 rounds from an AK-47/AK-74) and hit nobody. A bullet travels in a straight line (minus bullet drop), and that line is the diameter of the slug. If it doesn't intersect something, it's not going to hit it.

Unfortunately, what we see in the d20 system is unbelievably accurate fire. It's just so easy to hit, and even worse when you do what most people do and make firearms touch attacks (or use the "Armor as DR" variant). It is harder, full-stop, to hit somebody with a bullet than a sword swing. The trick is that you have a much larger engagement window (as Solaris rightly points out, the window in which you can shoot somebody is roughly 500 yards on down to 1 inch, while the window you can stab somebody is the length of the weapon plus your natural reach). Because it is so accurate, we never really see the disadvantages of firearms - namely wasted actions from not hitting, wasted actions from having to reload, and running out of ammo. Not to mention we never see the range issue (it gets geometrically harder to ht something the further away it is) because d20 engagement ranges are comically short.

So, if you're building a system from scratch, make sure to actually touch on these things. Guns should be less accurate (and primitive guns even MORE so). Reloading takes time (assuming a modern weapon, it's a free action to release the magazine, a move action to retrieve a fresh magazine, and a move action to reload the weapon...there's a full round gone). Bullets hit hard, but pistol or light rifle (5.56mm or less) actually wound people less than a sword or axe swing - modern weapons tend to overpenetrate and leave a small wound channel, while a sword swing will remove a limb without much effort (those tatami mats that samurai use for cutting practice since they mirror the resiliency of the human limbs? Yeah, a dull longsword will cut through one cleanly. Source). The cool thing with bullets is that their critical damage effects tend to be huge - they destroy important organs in the body, so you're looking at a huge critical hit modifier. This mirrors what we see in modern combat operations - it's not uncommon at all to hit a guy with several rounds and have him run away to get bandaged up with no issue (no critical hits), while the guy next to him will take a single bullet either go into shock and bleed out or die quickly from destroyed hearts, lungs, or nervous systems.

The last and most horrible thing for gunbunnies here is that what bullets really do isn't massive tissue damage. They ideally (as mentioned) do critical damage, or, FAR more commonly, send a person into shock, where they bleed to death while they're incapacitated. But shock tends to be a function of amount of damage vs size. All things being equal, a physically larger creature is harder to send into shock than a smaller one, given a wound channel of the same size (not always true, but true often enough to count for virtually "always", and true enough to form a mechanic upon). Thus, since bullets are generally made just big enough to do their job (incapacitate a man-sized target), they're going to be far less likely to do their job against a larger target. Just as a .22LR is fine against a woodchuck and will just piss off a deer, so too will a 7.62x39 be just fine against a man (or orc) and just piss off a troll or dragon. The bigger the bullet, the harder it is to carry ammo, resupply, manufacture, and control the shot while you're firing. So a sword will "scale" better against larger creatures, since they'll still be carving impressive wound channels (like here), while a bullet isn't going to generate a larger wound just because it's hitting a bigger creature. So the guy with the light-caliber rifle who can engage Orcs or goblins isn't going to do much at all against the Ogres and trolls. And it's VERY difficult to carry multiple weapons - there's a reason almost nobody in the real world carries more than 1 long weapon and one sidearm.

So, I can completely see where swords are still useful. Close-quarter battle situations. Extended or furious combat (who wants to be vulnerable for a round+ while you reload?). Combat against larger-than-man-sized creatures. People who want to hit more than 1 out of every 4-5 attacks. And that's not even taking magic into account (magic doesn't "take" on guns or bullets, for example).

[Solaris]

But you have to get the shot off without being disarmed, disabled.. stabbed whatever. You are trying to get a firearm have the business end pointing at your adversary before you fire, your adversary has to stay out of the line of death.

Go for the gun, *stab*

Aim with the gun, *Wrist block, step etc, stab*

Though it is not an everyday situation when we talking about PCs and appropiate challenges that inherent advantage melee has in melee range should be enough to use as a balancing point.

So using a firearm should provoke an attack of opportunity. That keeps them deadly within maximum range; But risky to use whenever you are in someone's threatened area. Keeping Melee weapons useful and effective, and letting the firearms really shine at range.

Uh, what? No. Drawing a firearm is as quick and easy as drawing a sword, even moreso if you have it on a sling. If you train with your weapon for any appreciable length of time, it's second nature. It's expected for a trooper to be able to take his weapon from amber to red-direct in about the time it takes for most normal people to think "Oh, crap! That's a-".
Not to mention we walk into a fight with our rifle already at the high-ready. The military is surprisingly genre-savvy about these action movies.
Aiming for a guy at point-blank? That takes less than the time it takes to blink an eye with a trained fighter. It's a reflex literally drilled into us from hours and hours and hours of training. When the guy's expecting the fight, like I said, he walks in at the high-ready and is in effect already aiming at the swordsman. All he has to do is pull the trigger. You really can't say that, all other things equal, someone with a sword would be able to step in and attack a rifleman faster than the rifleman would be able to start shooting at him.
Bear in mind, I'm talking about military carbines here. Rifles are a bit more awkward and ungainly, but even the M16 (which we 'affectionately' dubbed "the Musket") can be short-stocked into what I would consider a Medium firearm. The M249 and the M240B... Well, I wouldn't place bets on the gunner getting it aimed before the dude with the sword gets his choppa on. They're both heavier than the M4/M16.

You're better off arguing game balance if you want to provoke AoOs. Pistols and carbines should only take penalties to-hit on account of their sights not being particularly great for point-blank melee range (it's hard to look down a sight when you need your peripheral vision) and general nature of their function, but they don't aren't any riskier to use than a sword or an axe. You definitely got a good argument for rifles and crew-served weapons, though.

Does a gun trump everything on the contemporary battlefield?

Of course!

Do you find zombies, golems, ghosts, and physiological paragons with immunity to critical hits on the contemporary battlefield?

Hm, no.

A gun is basically a repeating crossbow with better stats and the same disadvantages. It'll suffer far less at a distance, but you'll never get to use your herculean strength modifier... Unless you throw it at someone, of course.

True, but you can't put armor-piercing, incendiary, or explosive rounds in a repeating crossbow.

Here's the thing: swords never need reloading.

Now, under normal d20 rules, people don't think about the inaccuracy of firearms. Yes, that's right...inaccuracy. Look for a moment with Teh Google at accuracy statistics by FBI, police, and military members for close-range encounters. They're terrible. A 15% hit rate is excellent, even at point-blank ranges. It's a lot harder to hit when you're moving and the other guy is moving. Physics demands this.

If you're 3 feet from the other guy and swinging a sword through the space where he is, he has to vacate his entire body from that space or be struck. If you're 3 feet from the other guy and pointing a pistol at him (say, firing from the hip), you have about a 15-20-degree arc window where the muzzle can move from side to side before you miss him completely. It's not at all like it is in Modern Warfare 2 or something - it's actually very difficult to shoot at and hit a person and anything more than room width. There's plenty of eyewitness accounts from Iraq and the Stan where an insurgent would hose down an entire room with full-auto fire (30 rounds from an AK-47/AK-74) and hit nobody. A bullet travels in a straight line (minus bullet drop), and that line is the diameter of the slug. If it doesn't intersect something, it's not going to hit it.

Unfortunately, what we see in the d20 system is unbelievably accurate fire. It's just so easy to hit, and even worse when you do what most people do and make firearms touch attacks (or use the "Armor as DR" variant). It is harder, full-stop, to hit somebody with a bullet than a sword swing. The trick is that you have a much larger engagement window (as Solaris rightly points out, the window in which you can shoot somebody is roughly 500 yards on down to 1 inch, while the window you can stab somebody is the length of the weapon plus your natural reach). Because it is so accurate, we never really see the disadvantages of firearms - namely wasted actions from not hitting, wasted actions from having to reload, and running out of ammo. Not to mention we never see the range issue (it gets geometrically harder to ht something the further away it is) because d20 engagement ranges are comically short.

So, if you're building a system from scratch, make sure to actually touch on these things. Guns should be less accurate (and primitive guns even MORE so). Reloading takes time (assuming a modern weapon, it's a free action to release the magazine, a move action to retrieve a fresh magazine, and a move action to reload the weapon...there's a full round gone). Bullets hit hard, but pistol or light rifle (5.56mm or less) actually wound people less than a sword or axe swing - modern weapons tend to overpenetrate and leave a small wound channel, while a sword swing will remove a limb without much effort (those tatami mats that samurai use for cutting practice since they mirror the resiliency of the human limbs? Yeah, a dull longsword will cut through one cleanly. Source). The cool thing with bullets is that their critical damage effects tend to be huge - they destroy important organs in the body, so you're looking at a huge critical hit modifier. This mirrors what we see in modern combat operations - it's not uncommon at all to hit a guy with several rounds and have him run away to get bandaged up with no issue (no critical hits), while the guy next to him will take a single bullet either go into shock and bleed out or die quickly from destroyed hearts, lungs, or nervous systems.

The last and most horrible thing for gunbunnies here is that what bullets really do isn't massive tissue damage. They ideally (as mentioned) do critical damage, or, FAR more commonly, send a person into shock, where they bleed to death while they're incapacitated. But shock tends to be a function of amount of damage vs size. All things being equal, a physically larger creature is harder to send into shock than a smaller one, given a wound channel of the same size (not always true, but true often enough to count for virtually "always", and true enough to form a mechanic upon). Thus, since bullets are generally made just big enough to do their job (incapacitate a man-sized target), they're going to be far less likely to do their job against a larger target. Just as a .22LR is fine against a woodchuck and will just piss off a deer, so too will a 7.62x39 be just fine against a man (or orc) and just piss off a troll or dragon. The bigger the bullet, the harder it is to carry ammo, resupply, manufacture, and control the shot while you're firing. So a sword will "scale" better against larger creatures, since they'll still be carving impressive wound channels (like here), while a bullet isn't going to generate a larger wound just because it's hitting a bigger creature. So the guy with the light-caliber rifle who can engage Orcs or goblins isn't going to do much at all against the Ogres and trolls. And it's VERY difficult to carry multiple weapons - there's a reason almost nobody in the real world carries more than 1 long weapon and one sidearm.

So, I can completely see where swords are still useful. Close-quarter battle situations. Extended or furious combat (who wants to be vulnerable for a round+ while you reload?). Combat against larger-than-man-sized creatures. People who want to hit more than 1 out of every 4-5 attacks. And that's not even taking magic into account (magic doesn't "take" on guns or bullets, for example).

Dude's right, but I'd call reloading a move action for a trained trooper. I'm on the slow end, and I can do it in about four seconds (this is dropping the old mag, not sticking it in the pouch). Most guys I've met can swap out magazines in approximately two-three seconds without taking their eyes off their targets.

The two biggest points people should take from SwordGuy are the inaccuracy and the bad scaling damage. The military's change in paradigm from large, accurate rounds to a mass of fire came about in part because of recognition of the fact that it's often hard to nail your target - so spraying him with a burst of bullets helps your odds tremendously.
I got a peashooter M4 carbine, and I gotta put a couple of rounds into a guy if I want him to go down. There are very few armored vehicles you can kill with an M4 (vehicle gunners, on the other hand...), as the little bullet simply lacks the stopping power to do significant damage to something mechanical. Sure, you might get lucky, but I'd bet on the APC before I'd bet on a squad of riflemen armed with 5.56mm carbines.

[blackseven]

The mistake most people make about D20 Modern firearms' lethality is that they look solely at weapon stats, see that a pistol is 2d6 and a rifle is 2d8, and go "that's weak, you can't one shot anyone but a mook."

The thing is, in D20 Modern, your Massive Damage Threshold (MAS) is equal to your CON score, instead of 50 like in D&D. With things that increase weapon damage (mostly feats like Burst Fire or Double Tap), or a crit, you have a great chance of putting someone, even high level with full HP, down with a single shot (unless they have really high CON or took MAS increasing abilities). OTOH, if you fail the Fort save for taking MAS, you don't die, just drop to -1 (unless the shot's damage dropped you lower).

You also have to realize that by the rules, you're squeezing off 1 shot per 6 seconds. That's a good amount of time to steady, (re)aim, and squeeze, even with movement before. This explains the "accuracy" compared to real life (a police officer will probably have emptied way more shots by 6 seconds.)

Finally, a fighter with high (16+) STR and a Greatsword still outdamages a gun user (assuming D20 Modern Gun stats and Feats), even discounting magic.

At level 1, the Gun user (let's say with a Rifle - 2d8 damage, and 80ft range increment) probably has the advantage. He does 9 damage average, and the fighter needs to get to him.

As the Fighter's level rises, gun user's advantage falls. The fighter's damage and HP scale up: the gun user's damage rises a little (couple feats) and his HP goes up, but thanks to the wonders of Power Attack and 2H weapons, the fighter quickly gets to one-shot damage. It becomes a matter of Fighter HP out pacing gun damage increases.

[Sir Sanguine]

Day-um, Swordguy. That's really extraordinarily helpful and I could see all of that applying in my game. My thoughts were that if you wanted to hit something right next to you with a melee weapon, you can: it's automatic. (Unless the target actively tries to parry the blow or its armor negates it) Having automatic hitting not be the case for firearms would be a great way to balance them. Also, it's great that there is actually a scientific reason to use swords rather than guns against a big thing like a dragon.

In conclusion, I think I'll just incorporate the whole of your post into my game.

[Waargh!]

Nope. In melee range a gun would also hit automatically. I can even hit somebody within 5 meters with a modern gun. Imagine a trained guy. Yes, it is not that easy hitting somebody from far away in the middle of a battle while he is running, but you wouldn't even get the chance to attack him with a sword... Seriously there is no comparison.

What swords offer (and many games forget)? The offer defense. You can parry and block attacks with a sword. Or keep enemies at bay. If a monster jumps on you then you are dead if you cannot block its attack. A sword will be more useful for that. Cut it in the air, even a little to ruin its attack. And shields and armor are useful even today. They are used. Armors not so much on humans but they are used for vehicles (tanks). The idea is a same. If the monsters are huge and could crush your armor, then you wouldn't wear one. If there attacks can be stopped by armor, everyone would wear one.

As for killing a dragon or a troll. Just put some explosive bullets or use a bigger diameter bullet and say goodbye to them. Launch a heat seeking missile on that fire breathig dragon and kaboom. Were a sword would have more difficulty cutting through. And consider fighting a stone golem which is practically immune to swords. Plus dragons...you know...fly. But will characters be able to have big guns or just small diameter pistols?

But even still, swords were evolved after the medieval era. So characters would bring more modern swords if they had to. They would bring modern armor as well. All kind of technology that would give them a much greater advantage. Why limit the equipment to firearms?

So, what you can do is make modern fighters in a fantasy world. They will use modern melee and ranged weapons. And of course, modern armor. Imagine if batman had to resort on using plate armor. No. They would still act as fantasy heroes because they would use melee weapons. Maybe the would be enhanced or much ligher and much more effective. But the fighting style would be the same. The would parry, block, evade attacks as they did back then. They would use big guns and firearms when they had the chance.

Remember at all eras that melee weapons were used, ranged-based fighters used them as well. If somebody charges you with a sword and you are holding a bow he would cut through you. Musketeers in the beginning fired a couple of shots and charged in others. Most casualties were in the melee part.

Even worse, warfare has changed. What people would do today is find were the dragon lives and bomb its nest. Or use a sniper rifle to take it out while it flies proudly in the sky. The destructive power of modern weapons is much greater. Killing anything is so much easier.

But all of this can be fixed by planning exactly what equipment you will allow...

[Cursedblessing]

True, but you can't put armor-piercing, incendiary, or explosive rounds in a repeating crossbow.

Actually you can. Brilliant energy Flaming Explosive Crossbow bolts. Costs 98K for 50 but why do that when you could be a wizard and screw the rules.