DPMS LR 308 buffer not rattle, can it make light primer strike

[Tony nguyen]

I build lr 308, lower is DPMS LR 308 , I have problem first shot is bang, over gas and next shot is miss fire light primer strike

I check buffer is not rattle, what can I do to improve?

[98Z5V]

Need more details on the rest of the gun, Tony.  Details like this:

 

[Albroswift]

Hello, Tony, welcome.

Lots of info, photos, and please introduce yourself.