AR 10 not picking up round

[kz45]

I little back ground,I have a dpms 308 that was a mid length gas, had it moved to rifle gas, 18" threaded for comp, I love how it feels, its way softer, but now it won't pick up the next round, what is the fix? low mass buffer/spring, lightened carrier, the best I can tell the gas block is not adj.

[ken hebert]

load one round and see if it locks back?

you sure the gas block is aligned over the port completely? barrel nut is lined up correctly? if not then it will put the gas tube slightly off center of the carrier key and could possibly lead to a malf, and premature wear on the tube.

top of my head you sound undergassed. (eat some beans) What size gas port did your gunsmith drill in the barrel?

heres a recent topic with some of the same probs: http://www.brianenos.com/forums/index.php?showtopic=110782&st=0&p=1261165&fromsearch=1entry1261165