You know, this is one of my many arguments against gun control that of course the antis don't get.
Maybe I am wrong but, in an environment where all guns are illegal, the easiest gun to make would be a full auto SMG. Look at the Grease Gun. Look at the Sten. Look maybe at the PPsH.
So if you are making black market guns are you going to try to make a repro of a Model 29? Nope. How about a 1911? Nope. How about a HK P7? Nope.
You are going to get some springs, some pipes, a torch, a welder and you are going to craft up a Sten.
This guy did it...so could many many people on this board.
So from that it follows not only "If guns are outlawed, only outlaws will have guns". But, in my opinion "If guns are outlawed, only outlaws will have guns...and they will all be homemade Sten guns!" Have fun going down town anti folks when the gangstas all have Stens and you got Jack!