AR Sponsor
Posted: 4/16/2012 5:55:55 PM EDT
| So my buddy has a DPMS upper with a heavy profile barrel and carbine gas system. Complete upper and bolt new from the factory. The bolt carrier wore out its first set of rings within a couple hundred rounds. Ok we thought maybe just some bad rings. Put a new set in and bam within 120 rounds rings are wore out again. On Saturday and Sunday we went to a rifle class, went through at least 600 rounds of rifle ammo but this time with a bolt out of his old beat to dirt bushmaster, rings are fine. He has used various brands of ammo, Federal, Remington, herters, ultramax, and probably several more (the second set of rings was only Remington ammo first set no Remington). Havent been able to check headspacing yet. No blown primers and the gun cycles fine. Groups are consistent. We are sure it’s the bolt as the bushmasters’ is still fine but what could cause this? Out of spec bolt? Thanks for the help in advance. |
|
Remove the bolt from the bolt carrier. Visually check to make sure that the inside of the bolt carrier has been hard chromed and smooth, you will also see inside (backside) of the two exhaust. on the right side of the carrier. When you put new gas rings on and reassemble the bolt carrier assembly, try rotating the bolt in and out of the bolt carrier. When the bolt rotates in and out of the bolt carrier, the gas rings will pass by the two exhaust port holes on the right side of the carrier. When the gas rings rotate by the exhaust port holes, it should pass by the exhaust ports smoothly (not catch on anything).
CY6 Greg Sullivan "Sully" SLR15 Rifles TheDefensiveEdge.com (763) 712-0123 |
AR Sponsor