Heavier weight or heavier spring?

[Chance]

Please post up feedback from supplier when you get it resolved.

 

[Tombs]

Please inspect the brass carefully after it's removed from the chamber.

I'd go as far as to paint a case and the bullet with a sharpie, then hand load it into the chamber, and extract it. You're going to get a LOT of information about what is going on from that.
But please be careful doing this with loaded ammo. If the gun is this out of spec, I'd have serious concerns that you may get a bang.

 

[Scuba591]

Please post up feedback from supplier when you get it resolved.

just got an email from Bear Creek Arsenal.... they could not duplicate the issue. They ran a full magazine using their ammo. I’m confused now. I’ll try different ammo... not sure it will change anything. After that, I’ll build another with a different lower, stock, spring and BCG. I’m going to call them tomorrow, maybe I just get a refund.

 

[Chance]

just got an email from Bear Creek Arsenal.... they could not duplicate the issue. They ran a full magazine using their ammo. I’m confused now. I’ll try different ammo... not sure it will change anything. After that, I’ll build another with a different lower, stock, spring and BCG. I’m going to call them tomorrow, maybe I just get a refund.

Thanks for the update. Puzzling for sure.

 

[DadSmith]

Maybe your buffer spring is to weak. Try changing it if you have not yet. Wolff springs are good ones, and reasonable price.