Just how difficult is it to manufacture automatic weaponry from scratch?

[S&Wshooter]

Originally Posted by funkychinaman

Wouldn't it be easier just to make an automatic nail gun? It's like something the A-team would whip up in a rousing montage. And all you'd need would be a hardware store.
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Yeah, but it would have insanely low stopping power. It wouldn't have the same kind of force behind it as a bullet does, and there most likely wouldn't be much cavitization. I bet they'd have awesome penetration if you could get enough power behind them, though