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Marred Bolt Face - Replacement?

Mike Lum

Cleaning the bolt face yesterday and noticing that primers are marring into the steel near the pin.
If you look close as it starts into the carbon ring you can see how its worn into the steel and it gets deeper near that pin.

Tikka T3x 22-250 with just over 1500 rounds through it.. time for a replacement?
Barrel can't be in much better shape after that many rounds...

Opinions?
20230124_105515.jpg
 
I'm not sure from that photo, but it looks like a good scrub with your favorite gun solvent may be worth a try.

I cannot say for sure, but it doesn't look like the typical pattern of gas cutting from a leak around the primer. Sometimes there really is damage there if a primer cup failed or a primer pocket leaked, but just guessing from that photo I would give cleaning a try.

At some point, it is good to know how to completely disassemble your bolt for cleaning and maintenance. If you don't have the tools or skills, it isn't difficult to tool up and learn, but if you don't have that desire any gunsmith can help you with that task. The ejector and extractor need attention every so often, and so does the firing pin spring assembly. It is worth it to learn how to keep these clean and running. YMMV
 
Thanks fellas, as yall pointed out there were definitely some loads put through it that blew primers, was hoping that the damage won't be bad enough to cause problems down the road.

This was the reason behind pulling the bullets and result of my other post in regards to the accidental discharge.. fun times...
 
That appears to be etching, not build up. And yes, it is caused by hot gas under pressure leaking past the primers. It becomes more prevalent as the pressure increases.

the solution? Shoot only cases that are new, or near enough to where the primers still fit snug in the pockets. And stay away from the upper load window.

If you shoot any rifle long enough, it will start to exhibit this type of damage IF you continually to use cases more than a few firings and shoot in the upper load window. I do it all the time. Thousands of rounds of “all the time”

I live with it,
 
jackieschmidt said:
That appears to be etching, not build up. And yes, it is caused by hot gas under pressure leaking past the primers. It becomes more prevalent as the pressure increases.

the solution? Shoot only cases that are new, or near enough to where the primers still fit snug in the pockets. And stay away from the upper load window.

If you shoot any rifle long enough, it will start to exhibit this type of damage IF you continually to use cases more than a few firings and shoot in the upper load window. I do it all the time. Thousands of rounds of “all the time”

I live with it,
Click to expand...
This is how loose the primers were...

Hammer style bullet puller - Accidental discharge.

As the title suggests.. finally had this happen after years of using a Hammer style bullet puller. Basic scenario was this - Pulling bullets form a loaded lot that was blowing primers due to too many reloads and lack of tension in the primer pockets. Idea was to save the powder from them at very...
forum.accurateshooter.com
 
Mike Lum said:
Thanks fellas, as yall pointed out there were definitely some loads put through it that blew primers, was hoping that the damage won't be bad enough to cause problems down the road.

This was the reason behind pulling the bullets and result of my other post in regards to the accidental discharge.. fun times...
Click to expand...
A few years back there were Winchester primers that would blow around the periphery at max charges.
I've seen a few rifles with complete rings of damage but it's not until damage is bad that it affects normal loads.
Here in NZ it put a few chaps right off Winchester primers.

The worst I saw was in a Tikka 270 being pushed hard, real hard and ultimately the owner needed the bolt refaced.
 
Homerange said:
A few years back there were Winchester primers that would blow around the periphery at max charges.
I've seen a few rifles with complete rings of damage but it's not until damage is bad that it affects normal loads.
Here in NZ it put a few chaps right off Winchester primers.

The worst I saw was in a Tikka 270 being pushed hard, real hard and ultimately the owner needed the bolt refaced.
Click to expand...
Now we know why those are the only ones left available on the shelves here in Canada!
 
jackieschmidt said:
That appears to be etching, not build up. And yes, it is caused by hot gas under pressure leaking past the primers. It becomes more prevalent as the pressure increases.

the solution? Shoot only cases that are new, or near enough to where the primers still fit snug in the pockets. And stay away from the upper load window.

If you shoot any rifle long enough, it will start to exhibit this type of damage IF you continually to use cases more than a few firings and shoot in the upper load window. I do it all the time. Thousands of rounds of “all the time”

I live with it,
Click to expand...
I agree. The face looks etched, along with some carbon buildup. It needs the face cleaned up.
 
rijndael said:
Stepping back a bit, if it's not gas leakage, how else do you get buildup around the primer hole?
Click to expand...
I just cleaned a bolt face yesterday that looked similar after just 150 rounds.

If I had known it would have been helpful, I would have taken snapshots. The material was stubborn but scrubbed off and there was no erosion or gas cutting under it. The user had never cleaned his bolt because he didn't know he should.

Under the forces and pressures of the bolt face during the cycle, that space between the primer cup radius and the chamfer on the primer pocket becomes a space where lubricants, solvents, and gases can pile up and condense. There is sometimes gas leakage around the primer that is less serious than gas cutting and is considered normal. Those small gas escapes combine with whatever else is there and become something close to an organic polymer like a varnish mixed with oxides. Hoppes has a good chance of breaking it up with some elbow grease.

I have no opinion of the odds that the OP's bolt face will clean up or not just based on the photo, but time will tell.
 
Mike Lum said:
Cleaning the bolt face yesterday and noticing that primers are marring into the steel near the pin.
If you look close as it starts into the carbon ring you can see how its worn into the steel and it gets deeper near that pin.

Tikka T3x 22-250 with just over 1500 rounds through it.. time for a replacement?
Barrel can't be in much better shape after that many rounds...

Opinions?
View attachment 1403573
Click to expand...
As others said it has to be gas leakage erosion. You knew the primers were leaking and you continued to shoot hot loads.
 
Stripped the bolt as suggested and gave it a good go, cleaner wouldn't touch the fouling and I didn't want to mess around with a wire brush so I did the same I would with a barrel I can't patch out any more.. JB's.

Didn't take much to get it off there, some pitting still showing but it looks like there may still be some life in it..
20230124_151605.jpg
 
That tiny mark at 11:30 in the photo is about typical for a rig with 1500 rounds on it. Can be worse, can be better just depending on your habits with respect to brass and pressure levels.

I see you removed the ejector for the job, which is good to make sure there isn't harmful crud down there that ruins the spring prematurely. Ejector springs and extractors need some love every now and then, as do firing pin assemblies. Glad that had a happy ending.
 
Coyotefurharvester said:
Would bushing the bolt face and new brass cure the ailment and the cause?
Click to expand...
Considering that brass was throwing primers and had a head separation, before i tossed it all out. I am pretty confident new brass will cure the Cause. The "ailment" as you put it was poor decision to keep loading it... note the secondary band starting to form on the brass above the case head in the middle picture if you follow the link over the the second post.
 
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