Here's the 6.8 upper I'm putting on a Stag-68 lower. I've already put about 475 rds through it while the upper with the upper installed on either my Bushmaster of Colt lowers.
Top: With scope mounted
Middle: Scope removed, BUIS folded down
Bottom: BUIS deployed
What it started as.
Upper group:
Colt M4 upper receiver
PRI Gas Buster charging handle
LMT enhanced bolt carrier
Bolt supplied by Randall Rausch of www.ar15barrels.com
Bushmaster firing pin, bolt cam pin and firing-pin retainer pin
PRI folding front sight assembly (stainless steel gas tube pin included)
Troy folding rear sight assembly
RRA midlength gas tube
PRI midlength carbon fiber free float handguard
PRI/MSTN Quiet Control muzzle brake
Rock Creek stainless steel blank turned by Randall Rausch of www.ar15barrels.com
Leupold Mark 4 PR/T 1.5-5X20mm scope
Larue SPR/M4 scope mount