Let me start this off i am no expert. If that isn't obvious of this post. I have 3 AR-15s I have built. First one still runs perfect. My other 2 one rifle chambered in .50 beo and a pistol chambered in 5.56. They are both as it appears to me be the same issue, i believe the are short stoking. They chamber manually, fire, eject, and fail to strip the next round off into the chamber. The uppers do not have adjustable gasblocks. Ill rattle off the parts list as much as i can remember in each. I am stumped. Any help would be appreciate it.
Rifle 1 .50 beo
Apache arms upper and bolt carrier
Anderson lower
HERA USA CQR Stock
TacFire AR-15 USA Made Lower Parts Kit
TacFire AR-15 4.9 Oz. Heavy Buffer
TacFire AR-15 6 Position Mil-Spec Carbine Buffer Tube
Pistol
Apache arms upper and bolt carrier
Omni polymer lower
TacFire Mil-Spec Pistol Buffer Tube w/ Foam Insert
TacFire 3 oz. Buffer
TacFire Carbine length buffer spring
Rifle 1 .50 beo
Apache arms upper and bolt carrier
Anderson lower
HERA USA CQR Stock
TacFire AR-15 USA Made Lower Parts Kit
TacFire AR-15 4.9 Oz. Heavy Buffer
TacFire AR-15 6 Position Mil-Spec Carbine Buffer Tube
Pistol
Apache arms upper and bolt carrier
Omni polymer lower
TacFire Mil-Spec Pistol Buffer Tube w/ Foam Insert
TacFire 3 oz. Buffer
TacFire Carbine length buffer spring