This is it! I went ahead and reblued all of the bare surfaces and scratched areas. Then I assembled it and did some string-assisted test firing at the range. Watch the video below:
I put over 300 rounds through this gun and counted four light strikes. The light strikes could have been caused by cheap ammo or not seating the cartridge all the way, but regardless it ran like a champ. And the best part is that it actually ejects! This is a pistol with no extractor and no ejector and it sends empty casings six feet downrange every time! It works!
Here's my idea for a forward charging handle that could be used on an AR-based bullpup, such as the one that's being developed over at FOSSCAD.
It's a single printed piece that slides along the Picatinny rail on top of the upper receiver. When it is pulled back, one of the feet at the back actuates the catch on the rifle's original charging handle.