Post-TDM Arms Manufacture

[Raellus]

In doing research for a little side project, I came across this strange little late-WWII weapon...

http://en.wikipedia.org/wiki/Volkssturmgewehr_1-5

It's basically a fairly crude, semi-automatic rifle that fires the same cartridge, from the same magazine, used in the better known and overall more advanced Sturmgewehr 44 (a precursor of the original AK-47).

... and it got me to thinking about arms and ammunition manufacturing after the TDM. I've also been following the thread on bows and arrows and blunderbusses and that's not quite what I have in mind.

What other examples of simple, military grade weapons are out there? Canon already has the M-16EZ and the RL AR-15 is a similar concept. I'm looking for things that can be made in damaged factories, small machine shops, garages, and the like- weapons that are simpler and require less hi-tech materials than current, standard issue weapons but that could/would still be issued to military, paramilitary/militia units. I'm not talking single-shot zip gun type weapons. Somewhere in between an M-16A2 and a zip gun is what I'm looking for.