1-800 Regime Change will rely on an incredibly complex system of firearms, so much so that guns will have their own character sheets (well, maybe two per page, but it’s up there).
To do this, guns are made from a number of components. A popular and recent video game that used this system is the Borderlands series, but they did more of a cosmetic-driven approach rather than a mechanics driven approach.
Each weapon in 1-800 Regime Change has five core components used to derive its base statistics (attachments such as optics, silencers, underbarrel grenade launchers, bayonets, slings, and the like can then be added). These components are, in order of the bullet’s travel, lower receiver, upper receiver, chamber, and barrel, followed by a body that holds the whole contraption together. I’m not going to go into exact mechanics of how that works (not that I know that much more than Wikipedia on the subject so I wouldn’t exactly be arming terrorists, but it’s very complex and each part determines a crucial gun function such as fire rate, range, and ammunition feeding).
In addition to this, each gun is chambered in one of nine possible calibers. This is somewhat oversimplified, and rather than using real life ammunition specifications I’m going for a length of bullet generalization (Pistol, Rifle, Anti-Material) and a size of charge generalization (Low Caliber, Medium Caliber, High Caliber). Again, I’m not going too realistic since the game is more based on movies, books, and other games than reality itself, and because I’m willing to admit I don’t know much about guns, don’t want to look at/do ballistic tests, and basically am hoping to finish the project eventually.
Each piece will have a number of possible variations, most of which are available in all calibers (with certain modifications). There are probably going to be about six lower receivers, some of which have unique game functionality, five upper receivers (a couple civilian, more military), three chambers (which will probably be the least likely to scale with bullet size, and determine possible ammunition to be used), four possible barrel types (and five lengths), and a number of bodies that will probably run to about three per type of weapon (type of weapon is based on certain criteria, and there will be eight weapon types or so)
Let us look at the number of possible guns from this. 6 lower receivers times 5 upper receivers times 3 chambers times 20 barrels times 3 body configurations times 9 calibers times 5 weapon types once you account for invalid chambering/barrel configurations and reduce accordingly. This comes to about 146,000 possible weapons (disclaimer: Not a mathematician, probably will increase), which will usually be capable of being modified to fit certain roles better (stealth, long-range, stability, and mobility can all be increased by modifications). I’m hoping to have silencers, flash suppressors, muzzle brakes, pointers, optics, gun-mounted weapons such as grenade launchers, shotguns, or blades for appropriate weapons, bipods, tripods, stocks, grips, and different magazines available for each weapon as well, meaning that it would be possible to add a significant amount of customization even after this (converting an assault rifle to a light machine gun by adding a bipod/tripod and a large magazine). In addition to this, there could be modifications such as water cooling to further customize specific types of weapons. If you want to go for every possible configuration, the numbers get pretty large, since most weapons will support at least two attachments and some will support four (this is the upper limit, barrel, lower, lower, upper) and a sling which I’m ignoring since it’s not really important.
None of this is really final, as I’ll see more of a solid picture of it when I’ve implemented the system, but there will be a good number of possible components and configurations.