Barrel Extension Lugs Peening?

[ncshooter18]

I have fired 210 rounds through this AR and today I noticed some peening on the lugs of the barrel extension. Is this something to be worried about or is it worn in and not going to wear anymore?

[Gentleart]

Do you have a picture of you bolt/bolt lugs?

[markm]

Great pic... yeah... how do the bolt lugs appear?

[constructor]

I have fired 210 rounds through this AR and today I noticed some peening on the lugs of the barrel extension. Is this something to be worried about or is it worn in and not going to wear anymore?

That is just the bolt contacting the lugs due to carrier slop in the receiver. It won't hurt anything. The front of the extension lugs and rear of the bolt lugs are the important areas.

[foxtrotx1]

Interesting constructor, do they all do this or just some rifles in your experience?

[WS6]

SRC reliabolt time

[556BlackRifle]

SRC reliabolt time

LOL... I was thinking the same thing.

[markm]

I just checked 10 guns at my house here, and didn't see any that had this kind of peening.

[constructor]

Interesting constructor, do they all do this or just some rifles in your experience?

Not all have it. The cam slot in the carrier controls the line up. The bolt is pushing a round forward out of the mag. At the same time the resistance from stripping the round from the mag is trying to push the bolt back in the cam slot. It can't turn far because the head of the cam pin is in the track in the top of the receiver until it reaches the half moon cutout.
If there is any play in the cam pin, track in receiver and carrier slot the bolt can turn enough to contact the extension lugs.
It should not happen...not designed that way but a little clicking wont hurt. If you can hear the bolt lugs knocking as it passes through or they connect enough to slow forward movement of the carrier you should definitely find out why.