I was up at Creekside Saturday doing some function testing on my new build and it looks like the action speed is too fast to reliably lock back.  I thought it was short stroking, but then I tried Horseman's mags with some Wolff springs and they locked back.  So I borrowed his buffer/spring and my rifle started working like a champ.  So, does anyone know where I can pick up either a H3 or 9mm buffer near the Smyrna area?