Need suggestions for blown out primers/bolt face damage

R

Randall3rd

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Minuteman
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May 28, 2021
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NJ
#1
Could use some guidance on where to start as I am very new to bolt guns. Just returned back from a training course, first time out over 100 yards and had a blast! Had to end up calling it quits early as I was blowing primers out consecutively and it was jamming up the bolt with gunk and parts of primer.
I shot 110 rounds over two days, a few primers went the first day, then it got much worse the second day and I stopped. I have attached a picture of the bolt, I’m guessing I have some damage but not really sure what exactly I am looking at. The questions is, where would you start to fix this issue? Switch up ammo? Check for internal damage? Scrap the whole gun and go buy an AI? Need some suggestions on where to go from here, particularly if it’s even safe to continue using if I switch ammo? Thanks!

Ammo was factory Hornady Match .260Rem 130g, used 2 different lots
Rifle is a Surgeon built Scalpel
 
#3
We need more information about the rifle. New? Chamber cut around a specific bullet? Round count since last cleaned? And more...

JFR
 
#4
I purchased it used locally, less than 600 rounds total on it, less than 150 since last cleaning. It was a factory build from Surgeon in .260.

I was planning to go with a full cleaning scrub down, and head out to try different ammo as a starting point, should be ok to do that it seems.
 
#5
I'd like more info on the build, barrel and how the chamber was cut. I've shot thousands of H130 ELD-Ms though four different .260 bolt guns and have never popped a primer or had pressure issues, except when I had a carbon ring from poor cleaning.

ETA - Given your reply of 150rds since last cleaning, I'd suspect a carbon ring that's creating excessive pressure.
 
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#7
With different freebores I would make sure I wasn't jamming the bullet into the lands and causing pressure. Some people like super short freebores and that can cause issues with factory ammo. If bought locally maybe check back with seller.

And boltface looks fine. Clean it up and should be fine.
 
#8

I don’t have much info on the build unfortunately as it was a factory built rifle. I know it has a 24” Bartlein MTU barrel. Looks like a good cleaning is the way to start. So will go from there. Appreciate all the advice!
 
#9
Definitely give it a good clean but I would also find someone who knows rifles and can check it out and make sure what's going on. Maybe check OAL to lands with the 130s so you can see if they are jamming or not and causing pressure.
 
#10
Been shooting 260 for quite a long time, I would personally put a bore scope in it before cleaning to see if you can visually see something going on in there. Then I'd clean the hell out of it and find jam on it, Erik Cortina has a great video for finding jam without a bunch of crap on YouTube. Then Id shoot the same rounds on it with a chrono and see where they are running and if there were any pressure signs compared to what you had before... If you had prior speeds that would be good too...
 
#12
The more you pop the more eroded and gross the firing pin tip and aperture will become and even worse the popping will become in turn. Hopefully its not so eroded it will require bushing the bolt face to restore it, hard to actually tell from the photos but it looks alrightish.
Hornady brass is large primer so it shouldnt be a small primer pressure issue.
Were both lots popping or only one of them or did you not pay any attention?
 
#13
Your firing pin took a beating like spife said, see below. Kinda surprised the orifice isnt more messed up. Looks like there was a lot of gas leakage around the circumferance of the primer as well, especially at 9 oclock. Probably want to replace the pin. That shadow at 2 oclock looks weird too.

 
#14
Is it “ popping primers” or piercing them. I don’t see any pressure signs stamped into the base of the case.

Like a coupe of fellows above noted, my first thought would be to heck the end of your firing pin and see if it’s chipped up and has a too sharp point.

Just a thought
 
#16
I purchased a used precision rifle that did the exact same thing. It was cut for a specific round, I think an AMAX, and I shot Berger hand loads. I couldn't figure out what was going on until someone pointed out I might have some throat erosion. Luckily, the Surgeon should allow you to send it to them and cut & re-ream to give you a fresh chamber -- at least that's what it seems like I remember they did for a friend with a similar issue like you and I have.
 
#18
Headspace is very important here; it is the space between the case head and the bolt face. Even an excess of a few thousandths of an inch will give you blown primers and what seems like high pressure signs. What's happening here is that the bolt closes and the ejector pin pushes the cartridge all the way forward in the chamber. If there is more than a thousandth or two of headspace, the cartridge will be slammed back onto the now extended firing pin, from the pressure of firing, and the primer will be pierced. In a bolt gun, it is difficult to measure headspace, but you can get an idea of whether or not this is an issue, by putting a new, unfired cartridge in a case gauge, like Wilson, and using a dial indicator, (adapter available from Mike Bellm's T/C website; he has one adapter that fits all case faces and most dial indicators with standard stems), measure where the case is in relation to go/nogo on the gauge. Then put a fired case in the gauge and if it is significantly longer, say .008 or .010", headspace is excessive. This can be corrected by trimming the barrel in a lathe. If you reload your cases, you can avoid this next time, by not bumping the shoulder back much, if at all. This condition may be why the previous owner sold you the gun.
 
#19
Additionally, if the fired case is say .006" longer than the unfired case, it probably tells you that the headspace is .006" plus whatever stretch there is in the gun, (GIVEN THAT PARTICULAR CARTRIDGE CASE), on firing. DIFFERENT BRANDS OF CARTRIDGE CASES WILL GIVE YOU DIFFERENT HEADSPACES. Because the locking lugs on a bolt gun are lined up with the case face, the stretch will probably be too small to measure. In this case, I would say that the headspace is around .007", with a .001" springback after firing, giving you the .006" lengthening. Headspace here should be .001" to .002". This fired case, if only neck sized, might have the perfect headspace of .001". Unfortunately, if you reload, you'll have to fire form every case to get to this point; not pleasant, so I would have a gunsmith look at it and trim the barrel if possible..
 
#20
Last note, be careful who you take your gun to. If you explain the situation to him and he doesn't reply or has a puzzled look on his face, he has no idea ewhat you're talking about and he probably will be of no help. This problem first occurred in a T/C Contender that I had blown primer issues with, for years, primers blown and extruded around the firing pin,to the point I couldn't open the gun without slamming it against my knee. A gunsmith (in AZ), had no idea what the problem was, so I just didn't shoot the gun much. Years later, I was educated by Mike Bellm. His website is extremely informative on headspace and he would be my "go to guy" on this issue. He has many paragraphs on this topic and once informed, you'll see things quite differently, especially when it comes to reloading. I have no connection to Mike, just grateful for what he taught me on his website and I am passing what I learned to you guys, hoping it helps. Lastly, if you have sights that are dovetailed onto the barrel, or scope rings drilled onto the barrel and he trims it, these items will no longer be absolutely vertical. The barrel will twist more into the received to take up however much he trims off. Also forend brackets mounted on the underside of the barrel will be similarly affected
 
#21
I would start with what Rob said regarding a good cleaning and ensuring your bullets aren't getting jammed into the lands based on how the chamber was cut.
Another possibility... It may not be the gun at all. I had a very similar experience with my 260 about 3 years ago. Blowing primers and eroding my bolt face, even with mild loads (I reload). After a ton of frustration and wasted time, I finally figured out that I had a bad lot of primers which was confirmed on the manufacturer's website. They even reimbursed my primer purchase and the refacing of my bolt. Switched primers and problem solved. I would first try some completely different ammo before you go off and do something drastic.
 
#22
Ok…. Appreciate all the replies here. I went with a full Bore Tech clean out. Cleaned everything out, carbon, copper, chamber etc. Went out to the range today, used completely different brand of ammo. First shot seemed to go fine, second, blown primer, 3rd had odd imprints on the face of the case but didn’t blow the primer but jammed the bolt down. I called it a day after that. What was really odd was that none of the shots actually hit paper at 100 yards. No idea where they went. (Yes the rifle is zeroed etc, was hitting no problem last time I brought it out before I started having issues).

I spoke with the previous owner, he did not have any issues like this, total round count is less than 250, I am inclined to believe him based on the amount of guns he owns and that I bought several from him that are all excellent and shoot lights out. I only started having issues after I put 50 or so rounds into it.

I added some pictures, you can even see the imprint of the words on the bolt face. Some marking around 10 o’clock on the 2nd and 3rd shot. 4th is unfired. Fun stuff! Next stop is a gun smith it looks like. Any suggestions? NJ would be easiest.




 
#23
I would take a no-go gauge and see if the bolt closes fully on it. Also, are you sure the chamber is not 260 Ackley Improved?

 
#24
@bohem Josh at Patriot Valley Arms should be able to help and he is over in eastern PA so not too far. Give a call if he doesn’t drop in here.

 
#25
That bolt face looks awful. BTW ... I had a blown primer issue until I started trimming down my cases to valid trim length, and backing off my shoulder just a little further. Apparently I was "squishing" my cases into the chamber and that was blowing my primers.
 
#29
Thanks @Rob01

The bolt face should be cleaned up and scrubbed off. Same with the internals on the bolt and likely your trigger area too. Popped primers leak gas and soot everywhere.

The pin tip is likely cut up from the gasses and that will cause ruptures down the road even with ammo that doesn't have any issue.

The reason why it was popping primers isn't attainable from these pics and info but it's something that we should be able to diagnose with the ammo, rifle and your experiences all together.

As far as fixing the bolt, based on what I'm seeing the bolt face is likely fine. The firing pin would be more my concern at this point.

Feel free to contact us if you'd like me to take a look at the rifle. My first suggestion is to reach out to Surgeon about the issue and see if you can get some guidance from them as they've had hands on the rifle already.
 
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