Welcome to the high road.
My take is, everything can be produced, however the quality of production is only as good as your gear.
I suspect you amy be talking about some future where we cannot sustain our supplies, in which case revolvers would be king for one reason: we'd have to make our own black powder once again. Semi-autos may have cyclic problems with such powders, and it would definately foul the bejeebus out of them.
Black powder is not the safest thing to make, but it's the easiest thing to make, and can be made from ingredients around the house. It is a smelly process however, and the process of making the saltpeter would be outright hazardous if you do not have an indirect heat oven of some kind.
Thing is, man has thought of these things in the past, so look back to the pioneer days, then move forward to the smokeless powder era and it will all start to make sense.