Firearm noises are useally dubbed over in the editing suite or the sound studio using sound effects library recordings. So you won't get anywhere trying to recognise a firearm from the noise it makes in a film. Its the same with automobile noise, where they'l have a car chase scene & some 60s muscle car has a sound like a F1 car, or you'l have a Chryler Neone burble like a V8 without a balance pipe, just because the soundman thought it sounded good, or crossplys squealing like radials or vice-a-versa, or a FWD making RWD power-oversteer squeals. My old man was a award winning cinimatographer & you wouldn't beleive half the sh!t that went on. Actually with most action scenes they don't even have any mics setup & all the sounds are added afterwards.
Even most stunts are just edited together footage of lots of mundane little movements, like Stallone jumping off a cliff & falling through a tree in the first Rambo film. Which was put together from half a dozen different shots. The first of which would have been him jumping down a embankment a yard deep & then half a dozen shots of him falling through branches taken in a studio. So in reality there was ah heck all of a stunt. Really most action sequences are 95% editing & sound effects.