Just completed the first of two builds. This one is the 18" version, have the 20" upper almost complete. I went with MagPul FDE as a color choice. Parts include:
MagPul PRS Stock, MagPul Grip, Timney 3lb Trigger, DPMS associated lower parts kit, MagPul rail covers, Leupold MK AR 3-9 with FireDot TMR, and the Leupold MK2 mount. The free-float rail is YHM as is the FS. Lower is LRB with a Flat-Top upper of course. Sling is Specter Gear, 3-point.
FUNCTION: Placed 3 rounds in a mag... 1st round fine, second FTE, 3rd was fine. I stopped and replaced the extractor spring with BCM's extractor upgrade... meant to do it anyway. No more FTE's.
About every 3rd round I was getting GREAT ejection but inadaquate BCG travel. A few times the BCG failed to lock back. Readjusted the gas block twice and after about 25 rounds things looked good.
Loaded 5 rounds in a mag ONE AT A TIME and all 5 locked the BCG back. Loaded 2 rounds and it cycled fine locking the BCG back... I think it's all lined up now. The more I shoot the more the carbon will seal up any slight gaps between the barrel and gas block.
Hope to hit the range tomorrow to do more shooting and get it sighted in. I am attending MagPul's SDM/SPR class this next week, hope to get this rifle into the mix.