Got a Real-World Weapon, Armour or Tactics Question? Mk. XXVIII

[Blackhawk748]

Yes, but also the gas systems on most semi automatic rifles are carefully calibrated for the pressure of the round for which they were intended. Timing the whole process of the bolt unlocking, moving backward, extracting and ejecting the case, then coming forward just as the magazine spring has pushed another round up into position so the bolt can chamber it and lock before firing is not something you can really mess with all that much. Change the pressure curve and throw off the timing and you have bolts tearing cartridges, stovepiping rounds, closing on an empty chamber, and lot of other issues. All this independent of fouling in the gas system.

In short, you cant just load your empty .223 cases with black powder and expect the rifle to function as a semi automatic. I don't know if you could even design a gas operated semi automatic rifle for black powder. Blowback operated, maybe, but that would still need a carefully calibrated powder load for consistent burn time and chamber pressure.

I wrote Gas-Operated off on the fouling issue alone. Everything else just hammers that fact home. Blowback? Maybe, but I kinda doubt it. Gas? Hell no.

The Minie ball helped with fouling, as, after expanding, the ball would remove a lot of the fouling that the previous shot had deposited, thus preventing too much fouling from building up, making the gun easier to load. Nevertheless, the blackpowder still generates a lot more fouling than smokeless, and that can start to gum up the mechanism. That said, the metallic cartridge black-powder repeaters could be fired for more than "10-15 shots" before getting gunked up (I think it was more of a problem for those that used paper cartridges).

Early Mausers, Vetterli rifles (Swiss and Italian), even the first Lee-Metford rifles, used blackpowder metallic cartridges.

Glad to see my memory is still on point.

Problem #1 is a much nastier one. Black powder is easy to make if you know the recipe, while you can load most guns (Glocks being the most prominent exception - they'll explode) with cast lead bullets. Casings are harder to make, but are reusable. That's 3 out of the 4 essential parts for a cartridge gun. The last one's a doozy.

See, to make the cartridge go off, you need something that will explode when struck by the firing pin - in cartridges this is called a "primer", while loose examples are "percussion caps". These are not easy to make. Fulminate of mercury requires toxic (and generally difficult to find) ingredients, a fairly involved process, and not detonating it can be difficult. Potassium Chlorate is safer, but still not easy to produce. If you can't manage that, you'll have to revert to loose-powder flintlocks.

Once you've solved that, you can decide what your best options are. Black powder can't attain the same velocities as nitro can, so big, heavy bullets are the way to go. This means that your post-apoc setting will have a very "Old West" fell to the weaponry.

Funnily enough, I had a similar situation in a different post apoc setting I had made, this one I wanted America to be using Hall Rifles primarily and as it tutrned out the two Mercury Mines in America happened to stuck in very hostile areas. A rather amusing happenstance for me.

As for the primers, I remember reading (God knows where) that there was a lead based primer or something like that and they didn't like it because the thing was less stable than the Mercury one.

And I am very fine with Old West Post Apoc.

The earliest Maxim machine guns used blackpowder ammunition, and Maxim patented several devices to filter particulate residue from the guns. Which were rendered moot by the introduction of smokeless powders a couple years later -- but it is possible to design an automatic weapon that works well enough with blackpowder. However, as you pointed out, you can't simply take an existing weapon and expect it to work without fouling becoming a serious problem.

I believe most of these weapons do have the ability to be adjusted for different pressures, but that may require an armorer, and the consistency of the ammunition is still important.

I recall Ian talking about this on... InRange I think, and while it seemed like it would sort of help with the fouling problem (it wasn't really well tested) there would still be this obnoxious cloud of smoke in the way and I think that will always be an issue for Full Auto Blackpowder, that damn smoke is always gonna make quite the wall in front of you.