Etched bolt face. Opinions wanted

[bichettereds]

Hi all. While fire forming some brass today I noticed an odd sound. Looked at the bolt face and saw that I had pierced a primer. It etched the bolt face as well.

Is this just a cosmetic issue (bugs the hell out of me) or are there other concerns?

I don’t understand why this happened. I’m forming 6ppc cases from 220 Russian lapua brass and filled them to the shoulder/neck junction with 322 and seated the bullet long. Have done this several times with no issues.

 

[dstoenner]

You are probably OK. Looks like you could take a sharp knife to what looks to be carbon. My bolt I have been using for the last 10 years had some etched out holes around where the primer would meet the bolt. Never had any problems. But when I switched calibers and went to 6X47 Lapua that uses SR primers I had a lot of primer issues and lots of cratering. Sent my bolt to GreTan Rifles. Had it bushed. Busing got rid of the etched out places and now the primers look text book with no cratering. The Remington firing pin hole size with firing pin tip size has LOTS of slop in the tolerances. Greg is almost always 6 to 8 weeks backlogged. Fixing all of the Remington bolts 1 at a time.

David

 

[drover]

Cosmetic issue only. I don't like them either but I did get a bad lot of primers one time and etched a couple very similar to yours.

drover

 

[alinwa]

Hi all. While fire forming some brass today I noticed an odd sound. Looked at the bolt face and saw that I had pierced a primer. It etched the bolt face as well.

Is this just a cosmetic issue (bugs the hell out of me) or are there other concerns?

I don’t understand why this happened. I’m forming 6ppc cases from 220 Russian lapua brass and filled them to the shoulder/neck junction with 322 and seated the bullet long. Have done this several times with no issues.

your load was too hot.

It doesn't matter how many times you've done it..... that load, that day was too hot.

The damage is permanent. The steel is eroded away just as if you'd hit it with your oxy/acet and a rosebud cutting head.

IME the ring is from gas leakage around the edges of the primer, the case is shot, wrecked, chuck it....

The pierced (actually blanked, punched) primer is a secondary effect, it's another sign of high pressure but not the one that etched your boltface......the disc of primer material is most likely inside your bolt and may cause other problems.

You're fine but it's of course cumulative...... think of the little mud puddle in the road. Is it dangerous? Nope. But let it pothole out big enough and it like to bust your shocks.

 

[243winxb]

https://apps.dtic.mil/dtic/tr/fulltext/u2/a599210.pdf

Same flash hole size? Gov calls the flash hole a spit-hole. Gov test on 7.62 gi ammo.

For this experiment the spit-hole diameter was reduced from the mil-spec 0.078 in to 0.055 in. As
figure 4 illustrates, this reduction in area increased the force exerted on the primer cup by 20
times when compared to the no. 34 primer output.

Spit-Hole Effects on the Ballistics of a 7.62-mm Cartridge.

When the cartridge with reduced spit-hole area is employed, there is a noticeable difference in
the primer force response. The initial primer spike is greatly enhanced, with about 350% more
pressure in the primer pocket during initial output. This much pressure in the primer pocket
would not be desirable under any operating condition. The smaller spit-hole also resulted in the
main charge burning sooner when compared to the baseline M80. In figure 5, the initial rise of
the chamber pressure occurs about 50 µs sooner, and the peak pressure is reduced 1500 psi.

The M80 had a standard deviation (SD) of 5.98 m/s, while the modified spit-hole M80
had an SD of 4.17 m/s, a reduction of 30%.

 

[243winxb]

Bullet jam, more pressure? https://apps.dtic.mil/dtic/tr/fulltext/u2/a622138.pdf

Seems the bullet moves from just the primer firing?

 

[500Stroker]

Hi all. While fire forming some brass today I noticed an odd sound. Looked at the bolt face and saw that I had pierced a primer. It etched the bolt face as well.

Is this just a cosmetic issue (bugs the hell out of me) or are there other concerns?

I don’t understand why this happened. I’m forming 6ppc cases from 220 Russian lapua brass and filled them to the shoulder/neck junction with 322 and seated the bullet long. Have done this several times with no issues.

Plan and simple.
Your loads are to hot and gas is escaping from around the primer. Good chance the brass is now junk.
Get a new bolt or have the bolt face resurfaced and resize the firing pin hole, break in some new brass or you will have the same issue. Work must be done by an experienced qualified Gunsmith.
Good luck

 

[powderbrake]

Mine is not a ppc, but same problem.
It may be pressure or it may be the primers. I had a series of blowouts that etched my boltface, and it turned out to be primers that were faulty. (See the crack at the radius on the primer in the pic) The primers were replaced by the manufacturer, and GreTan repaired the bolt face and turned the firing pin. All is well now, and the bolt looks like new.

Having GreTan bush the bolt and turn the firing pin is a good idea even if you have no problems. Your coned bolt may already have a smaller firing pin diameter.

 

[243winxb]

Check loaded rounds neck diameter. Tight necks need turned brass. To little clearance and pressure will go up.

Bolt face ok as is. At least its ok in 223, 243, 30-06. I have a few from bad primers or using the wrong primer in 223.

 

[500Stroker]

View attachment 1075930 Check loaded rounds neck diameter. Tight necks need turned brass. To little clearance and pressure will go up.

Bolt face ok as is. At least its ok in 223, 243, 30-06. I have a few from bad primers or using the wrong primer in 223.

"ok as is" for what? Mixing paint?
Play it safe, have the firearm inspected by a knowledgeable smith.

 

[Uncle Ed]

bichettereds

A closeup photo of your case and primer that let go would tell us a lot more. A bad primer can cause your problem before saying its a hot load.

In powderbrake's photo above you can see his primer let go at its rounded edge. This is where bad primers cups leak when the cups are defective.

 

[jepp2]

and it turned out to be primers that were faulty.

Who was the manufacturer and primer size? I have had numerous failures at the rounded corner. Originally the Rem 9 1/2 of 30 years ago, more recently Rem 7 1/2, some older (the copper color) and some with the gold color. And most recently a Win LR primer. I am really getting gun shy of defective primers. None were max loads. On the 7 1/2's it seemed to be aggravated with slighly loose primer pockets.

 

[powderbrake]

As you have seen yourself, any brand or size can have a fault.

I would not normally mention the name of the vendor, but in this case the vendor responded promptly, and took care of the situation. In my case it was Winchester LR. I sent Winchester photographs of my bolt and the cases and the primers that had failed. Having the lot number of some of the primers was a big help. Starting off with a factual email, being courteous, I requested they kindly replace the primers and fix the bolt. They requested I send them my unused primers, which I did.
After they had received the primers and inspected them, they offered to repair the rifle if I sent it to them. Since it was a tuned Rem 700 action in a McMillan stock with a Kreiger barrel, I suggested I have the bolt repaired by GreTan and they agreed to that.

I had the bolt repaired, they sent me a check for the cost, and replaced the primers and then some. I was happy with their response, and satisfied with the results.

The biggest lesson I learned is "Identify each reloaded batch with the lot numbers of the cases, bullets, powder and primers". I even bought a Dymo label maker, and all that info is now on the top each batch of reloads.

 

[Nature Boy]

Who was the manufacturer and primer size? I have had numerous failures at the rounded corner. Originally the Rem 9 1/2 of 30 years ago, more recently Rem 7 1/2, some older (the copper color) and some with the gold color. And most recently a Win LR primer. I am really getting gun shy of defective primers. None were max loads. On the 7 1/2's it seemed to be aggravated with slighly loose primer pockets.

Win LR primers are below SAAMI min specs by 0.001-0.002", at least the batch I have is.

Combine that with a stretched pocket and a hot load and I bet you get what we see here.

I don't use reloading components from Winchester anymore

 

[Dusty Stevens]

Im sure glad they took care of you. Being nice on an email instead of a grumpy badass with a lawyer gets you pretty far these days

 

[fyrewall]

The OP did not say what kind of SR primer he was using, no photos of case with primer, or primer were provided. The attachments provided by 243winxb were of interest, our government (white lab coats) at work.

I have had 3 primer failures in 40 years of making ammo. Ultimately all were caused by pressure, either above maximum or excessive for primer. In in one event, the primer was not suitable for the task - a Winchester standard SR primer. Like, boom - smoke, hole in primer, stuck firing pin caused by primer material in bolt (removed by a pipe cleaner). Using SR primers with thicker cups solved the problem, CCI 41's, CCI 450's, Rem 7 1/2's. When primers are formed work hardening occurs at the radius.

Hard to believe that Lapua would make a case with a sub-size "spit hole" (ugly but descriptive). Other stuff, as mentioned, might have occurred. How about this one - a small pistol primer? As for Winchester primers, I quit using them some time ago. I contacted Winchester and asked them when my particular lot of primers were made, Winchester said that was "proprietary' info. One lot of Win LR primers appeared to be sub-diameter and could be seated almost no force while CCI 200's seated with normal force. I remember, in the late 40's and early 50's when my rifle loving relatives visited pawn shops to collect mostly M98 Mausers, they usually showed me one cause for rejection - a deep etched ring around an egg shaped firing pin hole in the bolt face.

The damage to the OP's bolt face is almost all cosmetic but sure points out the need to find out what caused it. The others look horrible - deep rings, chewed up ejectors and smeared brass. My 6.5X47 L bolt face looks new using CCI 41's, CCI 450's & Rem 7 1/2's.