Well, the bug bit, and a buddy of mine got a stripped lower a couple of weeks ago. I decided to build my own, largely from scratch. I'm having a few parts 3D-printed - specifically the ejection port cover/shell deflector. I'll be buying the barrel, but machining my own extension, receiver, bolt, carrier, and charging handle.
I'll keep y'all updated as I work through the build, but I'm doing a piston upper, with an ambidextrous ejection port/charging handle option - anyone else find the standard AR-15 rear-mounted charging handle kind of wonky?