M-15 bolt question/problem

[Hecklerusp45]

I have an Armalite M-15 that I have had for a year and a half. I have put a max of 800-900 rounds through it. I was cleaning it this weekend and found something odd. I was cleaning the bolt face and noticed that around the firing pin hole there is a ring where the primer sits against the bolt face. I had never paid any attention to this since I see it on my other semi-auto rifles, but upon closer inspection I noticed 3 or so small pits in this ring. The pits are so small that the sharp point of a safety pin will just barely go in. I called Armalite today and they said that sometimes hot gas gets around the primer and does this and that it is normal. I have never seen this happen on any other rifle and wondered what others thought about this. The same Armalite person said that a bolt typically only lasts 3000-5000 rounds. Could that be right? If I have to replace the bolt in the future, what are the odds that my headspace will be right?

[BigMo]

-the ring on the bolt is normal.
-the pits are more worrisome-- only because it indicates your ammo is leaking gas from the primer. Reloads with excessive pressure was my problem.
-eventually unless you stop the leaks- yes the bolt will need to be replaced. 3-5000 rounds is low for me-
-On AR's replacing the bolt is painless- it should headspace- no worries. That is due to the design of the AR.

[Hecklerusp45]

thanks for the reply. I have cut my powder charge down so I hope that there will be no more pits.

[Johnny in Texas]

You can go to Bench rest primers they have a thicker cup.

[Hecklerusp45]

You are right, they do. I will use some.

[rider]

Most of not all 5.56 military ammo has crimped and sealed primers. I would not handload AR ammo to anything hotter than the high end of .223 spec.

[joem]

I use only CCI or Federal primers in my reloads. They seem to fit tighter and seal better.

[RED]

I have the bolt from my old H&R M-16A1 that fired several (10k+) rounds mostly on Full Auto and mostly Milsurp factory rounds. It developed the same ring and some small pits but was never a problem. I can't get a clear pic or I would post it

[p246]

We have Bustmasters/LMT/Colts. All bolts on those run more than 5,000 rounds on them. If your worried buy the correct head space gauges and keep an eye on it. Take extractor off bolt before checking head space.

[Dan Shapiro]

Had the same issues, including an occasional pierced primer until I switched to Remington 7 1/2 Bench Rest Primers. Have had no problems since then.