The weapon firing 55 grains at 3290 FPS in FMJ form with cannelure, at 1-200 yards has been shown to be effective, so we shorten the barrel, probably increase the weight of the gun, and now look for special bullets at 2500 FPS to do about the same thing. The 10-12 inch pistols etc look pretty cool so you got that going for you, OTOH a pencil barreled 16-20 inch gun firing M193 55’s at 3100-3200 probably is as good or better than a 12.5 shooting 75 hornadys at 2300 from a 12.5. The emperors new clothes. I guess the army has to spend money.
