Time to change bolt?

[gemini1]

Went to the range last weekend with a couple of newbies. After a couple of hundred rounds, one of the guys shooting my AR15 had a FTF. When I inspected the the rifle, pulled the mag out, and the round that was supposed to get chambered came out as well, and I noticed that the tip of the soft point ammo I used was bent. Didn’t give it much thought. When I pulled the charging handle, an empty case got ejected! I just thought, maybe this caused the failure to feed, and didn’t bother to inspect the case (mistake!). Placed the rifle on the rest, since it was a bit hot and let the guys shoot the other rifle (308).
so after another couple of hundred rounds, we packed up and went home.
The next day, I started to clean the rifles, I noticed a piece of what’s left of a primer embedded on the bolt face. After removing the metal, and cleaning the bolt, I was looking at the bolt face and wondered, has the erosion gone that deep, that caused the primer to get blown out?
what do you guys think?
IMG_2104.jpg

edit: I already ordered a new bolt.

[Grendel Guy]

Aww, a bit of bondo and it'll be fine.

[G-forceJunkie]

Good god, what ammo are you shooting, handloads? I've never seen factory ammo eat a bolt face like that.

[gemini1]

Good god, what ammo are you shooting, handloads? I've never seen factory ammo eat a bolt face like that.

Both. But after I test a few select loads and figured out which is best for my rifle, I just load at the minimum, for plinking. I did have over 5k rounds down the tube, but being a BCM upper, I thought it could last a bit longer.

[turbolarry]

.... has the erosion gone that deep, that caused the primer to get blown out?
what do you guys think?

edit: I already ordered a new bolt.

A high pressure round against an eroded bolt face? Yeah, I'm gonna say some of the primer was more than happy to take up that extra space.
And I think the bolt face and ejector looks like straight up chocolate starfish ***!!!! Damn homie!!!!!
The new bolt should definitely help

[smoothy8500]

Over the years Winchester primers had some bad lots back in 2008 and again recently where the corner of the cup would fail and pinhole the bolt face.
images?q=tbn:ANd9GcSJBo0npTumXM4nQWIjjvSjts9n1u-Ycmr6cg&s.jpg

[ar15barrels]

Went to the range last weekend with a couple of newbies. After a couple of hundred rounds, one of the guys shooting my AR15 had a FTF. When I inspected the the rifle, pulled the mag out, and the round that was supposed to get chambered came out as well, and I noticed that the tip of the soft point ammo I used was bent. Didn’t give it much thought. When I pulled the charging handle, an empty case got ejected! I just thought, maybe this caused the failure to feed, and didn’t bother to inspect the case (mistake!). Placed the rifle on the rest, since it was a bit hot and let the guys shoot the other rifle (308).
so after another couple of hundred rounds, we packed up and went home.
The next day, I started to clean the rifles, I noticed a piece of what’s left of a primer embedded on the bolt face. After removing the metal, and cleaning the bolt, I was looking at the bolt face and wondered, has the erosion gone that deep, that caused the primer to get blown out?
what do you guys think?
IMG_2104.jpg

edit: I already ordered a new bolt.

That pitting is from hundreds of over-pressure rounds that were leaking gas around the primers for hundreds and hundreds of rounds.
You don't get gas cutting like that from "just" a few rounds.

[jsanch03]

Looks like my 91/30 bolt

[Devilock04]

Here you go

Complete Anderson Full Auto Bolt Carrier Group for $50

https://www.primaryarms.com/anderson-manufacturing-complete-m16-bolt-carrier-group-with-nitride-finish-am-10-08-m16-nit

[gemini1]

That pitting is from hundreds of over-pressure rounds that were leaking gas around the primers for hundreds and hundreds of rounds.
You don't get gas cutting like that from "just" a few rounds.

Thanks for the input Randall. Of the reloads I've done over the years, I've only done less than a hundred rounds that was at or a bit over the max recommended load. It was during the time I was looking for the best load my upper. The regular load I do for plinking is just at minimum. But lately I've been discarding a lot of my brass, where the area around the primer is black. So I guess the brass I've been re-using has gone bad.

[gemini1]

Here you go

Complete Anderson Full Auto Bolt Carrier Group for $50

https://www.primaryarms.com/anderson...-10-08-m16-nit

Thanks! I already got the BCM bolt I ordered also from Primary Arms.

[M1A Rifleman]

Thanks for the input Randall. Of the reloads I've done over the years, I've only done less than a hundred rounds that was at or a bit over the max recommended load. It was during the time I was looking for the best load my upper. The regular load I do for plinking is just at minimum. But lately I've been discarding a lot of my brass, where the area around the primer is black. So I guess the brass I've been re-using has gone bad.

You mentioned soft point bullets. Do you crimp your bullet in place? With SP bullets it’s possible they seat themselves too deep when in the mag during firing and upon loading into the chamber resulting in over pressure. I pitted an AR bolt onetime using SP reloads.

[imarangemaster]

In 20 years LEO, 7 years Military (much of that 27 years being an armorer), and 40 years building ARs I have never seen a bolt eroded like that. It is dfinitely not a Carpenter 158 steel bolt.

[jameshenry]

I used a primer pocket gauge and had to throw away a lot of "GOOD" brass. Also found some pockets that were shallow!

[gemini1]

You mentioned soft point bullets. Do you crimp your bullet in place? With SP bullets it’s possible they seat themselves too deep when in the mag during firing and upon loading into the chamber resulting in over pressure. I pitted an AR bolt onetime using SP reloads.

Yes I do crimp my reloads. The only time I did not, was when I was testing some loads, to see if theres any difference in velocity. But those were not SP bullets, and it was when I just started reloading.