>>42757943
I'm currently writing a fic where towards the end, ponies do get firearms, The weapons are pretty much rifles strapped on the side of ponies (or front) through a sort of specially made vest , a bit like pic related, and it would work with the vest being linked to the tail of the pony, and the movement of the tail being what decides if it fires, stops, puts the security or drops the magazine to insert a new one (which would be done by hoof by the pony.
I'm surprised to have never seen someone think of something like that in their fic (though someone probably did, I just haven't seen it yet), the closest thing to it is to my knowledge the guns in Fallout Equestria, but they use their mouths instead of their tales, which I always found dumb because what if you need to shout orders or just communicate? Doesn't seem practical.