The last major task I have is riveting the camming piece into position. The receiver otherwise is complete with grip mods done/installed and working fine. A few pesky problems to diagnose though.....
1. I can't manually pull the bolt back far enough with the cocking handle to eject a cartridge. The raised tab on the rear of the ratchet plate prevents the handle from going back far enough.....about 3/16th" shy. Ratchet plate installed where it needs to be less the tip of the cocking handle protrude in the ejection port. I think I simply ground off too much on the tip of the cocking handle when I notched it where it interacts with the tab on bolt carrier. Easy fix.
2. Getting the bolt back past the camming piece at the point of unlocking the bolt/barrel is now a bear. It was working fine after welding the receiver halves, so I'm confused as to what's causing the problem now.
-Barrel slides back and forth freely without binding under pressure from recuperator.
-Barrel installs and the door closes smoothly.
-No apparent sharp corners or obstructions noted in transition between camming piece ramps and the rails.
-At times I can hear the bolt disengage the barrel and the barrel return forward, but the bolt still resists being pulled to the rear.
-Tried several different bolt head and barrel combinations, no diff. All this with the top cover and feed tray removed.