Etched bf & jam

[hotload]

Gents,
After my last range trip I noticed what looks like an etched bolt face from leakage around my primers. Federal cases (308win) have only been loaded twice so I’m assuming this is because of pressure and not loose primer pockets. I’ve looked at case heads under a loop and seen no other signs of pressure.

I think this is happening due to too much jam into the lands. Chamber is cut using LRI’s “sniper reamer” for 165 smk. I measured a distance from bolt face to lands of 2.1770. My reloads using 175smk measure 2.230. means I was into the lands 0.05. I’ve backed off to a length of 2.220 which matches factory federal 175smk ammo but that is still a jam of 0.04 into the lands, which I’m concerned is still too much.

any advice?

 

[918v]

Sell all your guns and find another hobby

 

[Bradu]

.050" jam? I'm guessing the bolt is a little hard to close if you are running any kind of neck tension. I have to ask why you would want to run like that? If you chamber a round and need to extract a live round, I'm sure the bullet will stay in the barrel.

 

[hotload]

Sell all your guns and find another hobby

That’s great financial advice.

 

[hotload]

.050" jam? I'm guessing the bolt is a little hard to close if you are running any kind of neck tension. I have to ask why you would want to run like that? If you chamber a round and need to extract a live round, I'm sure the bullet will stay in the barrel.

You would think so, but no. No issues closing the bolt or extracting a live round. Though when I do extract a live round I can see the marks from rifling on the bullet jacket, which is what clued me into this in the first place.

 

[spife7980]

That’s etching? It looks perfectly formed. Can you feel it with a fingernail? Does it run away?
Put a new primer in the case, are they loose or can you still feel some resistance?

 

[hotload]

That’s etching? It looks perfectly formed. Can you feel it with a fingernail? Does it run away?
Put a new primer in the case, are they loose or can you still feel some resistance?

Yes. Can feel with fingernail. Looked at it under a hand lens too. Perfect groove.

Load is 45gr varget. 210m primer. Fed case. 175mk. Coal=2.820

 

[918v]

You are running a powder charge developed for Winchester commercial brass that weighs 156 grains and holds 58 grains of water in a Federal case weighing 176 grains and holding 55 grains of water and jamming it 50 thousands into the lands????

Are you fucking serious???

 

[El Cid 92]

Not trying to a smartass......

But did you work up to this load?? Or just picked a random starting place??

The listed info above shows that the load is compressed and your jamming it into the lands. Both moves are going to generate a massive pressure spike. The evidence is the severe etching of the bolt face. Thus living up to your screen name.

I'd suggest that you stop using this load in any manner. Return to reasonable load starting point and slowly and methodically work up a load that is jumped and not jammed.

You my friend are playing a game that has damaged your equipment and can cause harm/destruction if you persist in this manner.

Andrew

 

[918v]

To be fair its inside of the hodgdon data but its still at max.
View attachment 7075860

No it isn’t. Hodgdon’s data was developed in Winchester brass not Federal. Those two cases have different case volumes.

 

[spife7980]

No it isn’t. Hodgdon’s data was developed in Winchester brass not Federal. Those two cases have different case volumes.

I’m going to call myself a dumb ass and didn’t realize the federal in the description was for the primer. I tried to read fast but ended up reading too slow

 

[918v]

You’re not the dumass

 

[Steel head]

I’m going to call myself a dumb ass and didn’t realize the federal in the description was for the primer. I tried to read fast but ended up reading too slow

You’re not the dumass

I concur

 

[Long Range 338]

@hotload you are getting some harsh treatment but it is for your own safety. What is your reloading background? Either you are fairly new or overconfident. EVERYTHING affects your load. Change the primer, start over. Change powders, start over. Change cases, start over. Change bullets, start over. The only thing you can change without backing off your powder charge is seating depth (excluding jamming into the lands). You should find a mentor or take a class, there is a lot of knowledge transfer that only happens in person. Every reloading manual will tell you the maximum loads are for the exact components listed and that you should back off 10% and work you load up by testing yourself.
We are so used to good firearms and cartridges that we tend to forget that firing a cartridge is a CONTROLLED EXPLOSION going off 4 inches in front of your face! Good luck and be safe.

 

[Milo 2.5]

Let's see a pic of your primers on fired cases. Also, has that firing pin hole had a bushing job done?

 

[hotload]

I appreciate the criticism and input from those that care. My goal is to learn from this.

I have successfully reloaded for hunting rifles for 7-8 years now. Always safely. Never a problem until now.

In this case I worked up a load in half grain steps from 42gr with no signs of pressure. No brass deformation around the plunger, cratered primers, or sticky bolt.

It seems if I was in fact jammed into the lands as far as my measurements say I should have issue closing bolt and extracting live round. But I don’t. Easy in, easy out.

For the record I’ve abandoned this load until I sort out the issue.

 

[Long Range 338]

Its an old school method but I always check my seating depth by making a dummy round and using a sharpie to paint the bullet black and then seat the bullet out long enough to touch the lands. Then I adjust my seating depth until the bullet is no longer touching the lands, this is COAL. Seat another 10 thousandths and you should be good to go.
It is strange you were jamming into the lands and not having any difficulty closing the bolt or ejecting without bullets falling out. A picture of your primers would be interesting as well.

 

[hotload]

Let's see a pic of your primers on fired cases. Also, has that firing pin hole had a bushing job done?

This is the worst case of the batch. After a second look at them all there are a few with light plunger marks. This case has it between FC and WIN.

No bushing job

 

[Milo 2.5]

This is the worst case of the batch. After a second look at them all there are a few with light plunger marks. This case has it between FC and WIN.

No bushing job

Ok, if your bolt face was being etched as you say, the holes around your fired primers would be black from gas escaping. I take it is a Rem 700 bolt, have you owned it since new? How long has it looked like this? It would have started with pin holes in random locations, and steadily gotten worse.
Your primer looks good, no gas IMO, I say what you have is a shitty bushing job.
Primers would have been falling out.

 

[supercorndogs]

At 2.82 COAL, you are probably just barely touching with the 175SMK, if its the same reamer LRI used on my .308. I can't imagine you would be jammed .05 at that COAL.

 

[hotload]

Ok, if your bolt face was being etched as you say, the holes around your fired primers would be black from gas escaping. I take it is a Rem 700 bolt, have you owned it since new? How long has it looked like this? It would have started with pin holes in random locations, and steadily gotten worse.
Your primer looks good, no gas IMO, I say what you have is a shitty bushing job.
Primers would have been falling out.

This is a 700 bolt (tac30 action). I am original owner. The ring in first pic is from 30 or less rounds after last range session. It wasn’t there, and now it is. No bushing job on this bolt. Factory format from Stiller.

 

[Milo 2.5]

This is a 700 bolt (tac30 action). I am original owner. The ring in first pic is from 30 or less rounds after last range session. It wasn’t there, and now it is. No bushing job on this bolt. Factory format from Stiller.

I am no gunsmith, but I think I am smart enough to say that did not happen in 30rds of abuse, now I am not questioning you either. It is too perfect, and unless your fired brass shows signs of gas escaping, no way.
I think you have gotten some wayward advice in this post, have someone qualified inspect that bolt, because if it is by chance etched, it has been seriously compromised IMHO.

 

[hotload]

At 2.82 COAL, you are probably just barely touching with the 175SMK, if its the same reamer LRI used on my .308. I can't imagine you would be jammed .05 at that COAL.

That would explain why I can load/unload without trouble but have spiked pressure.

So the consensus here is start over in load, reduce coal, and have gunsmith inspect bolt?

 

[Bradu]

That mark on the bolt face isn't going to hurt anything. Odds are you had one bad one that caused that. I ran into a bad lot of Winchester primers that made the bolt face look worse than that before I noticed it. I also have a bolt look like that from a combination of loose primer pockets and a build up of carbon in the throat. There are threads about it all over the internet and that look a lot worse that people are still running.

 

[Bradu]

With that said, look through all your fired brass for that rifle if you haven't resized it or knocked the primers out. You may find one or two that caused this. You need to clean the barrel and measure where the lands are and start over. Back off the lands .015-020" and work your way up with your powder charge. Start at the book minimum and watch for pressure signs. It seems as if you picked a charge and just loaded it, that's a bad idea and a good way to fuck up a rifle or hurt yourself or someone nearby.

 

[hotload]

With that said, look through all your fired brass for that rifle if you haven't resized it or knocked the primers out. You may find one or two that caused this. You need to clean the barrel and measure where the lands are and start over. Back off the lands .015-020" and work your way up with your powder charge. Start at the book minimum and watch for pressure signs. It seems as if you picked a charge and just loaded it, that's a bad idea and a good way to fuck up a rifle or hurt yourself or someone nearby.

Appreciate the input. Load was worked up from 42gr. Was the most accurate of everything I tested so I went with it. Groups started opening up, so I figured the barrel must need cleaning. So I did and that was when I noticed the bolt face.

I think my system is breaking down at correctly measuring distance to the lands. Using Hornady coal tool I’m getting a number that seems very short, even though I’m tapping the bullet into the freebore/lands as instructed.

 

[Eddystone]

Appreciate the input. Load was worked up from 42gr. Was the most accurate of everything I tested so I went with it. Groups started opening up, so I figured the barrel must need cleaning. So I did and that was when I noticed the bolt face.

I think my system is breaking down at correctly measuring the distance to the lands. Using Hornady coal tool I’m getting a number that seems very short, even though I’m tapping the bullet into the freebore / lands as instructed.

Any chance that your bolt has a coating on it? The ridge looks like the primer, case contact has polished the bolt face and left a ridge of coating.?? I am not there, 2D picture and all, Ceracoate and such being common...

Ok I would then look at a carbon ring starting to form in the throat, as mentioned above, I have a 338 that the throat is exactly the bullet dia for my SMK, It is very sensitive to carbon, Gives the appearance of jamming the lands, when it is not. It is jamming the throat and carbon id, then bad things began even at minimum loads. Scrub the crap, carbon, out of the throat, and or get borescope to check throat condition. This is after eliminating all the other variables mentioned above. You mentioned the really short coal measured with your Hornady tools. You may be really close to the answer. If it is carbon, it is a MF'erto get out, or I just am a lousy bore cleaner, Hahaha I hope it is something simple.

 

[918v]

You need to learn about how pressure vessels work. Pay attention to the specific components used to develop the load data you are reading. You’re 3 grains over max in that FC case. If you want to load 45 grains, use a Winchester 156gr case. Just because you don’t see pressure signs doesn’t mean you're not exceeding max pressure.

Send your bolt to Greg Tannel to have it bushed. While it’s there, learn about how different components interrelate. How longer bullets seat deeper in the case and reduce effective case volume and how that raises pressure. How heavier cases have thicker walls and less internal volume. How different lots of the same powder can cause different pressures due to the variance in burning rate.

Study the feel of your bolt lift with factory ammo. Start with 147gr ball ammo and then move on to FGMM then to your handloads. You want to make sure your bolt opens as smoothly and easily as with these factory rounds. Any heavier means your load is excessive.

Don’t listen to dumfucks who make wild claims about this or that or how the brass is soft and such. The 100 FPS your gonna gain isn’t worth it.

 

[hotload]

At 2.82 COAL, you are probably just barely touching with the 175SMK, if its the same reamer LRI used on my .308. I can't imagine you would be jammed .05 at that COAL.

I took a harder look at my measurements and you’re right, I’m either just at the lands or slightly jammed. No more than 5 thousandths jammed if that’s the case.

Will call Tannel this week to get advice about my bolt face.

 

[Bradu]

I took a harder look at my measurements and you’re right, I’m either just at the lands or slightly jammed. No more than 5 thousandths jammed if that’s the case.

Will call Tannel this week to get advice about my bolt face.

This will answer your question about the bolt face. I'm case you dont know, Dave Tooley is a great gunsmith and talks about the etching in this thread. There are other threads along with other gunsmiths that will tell you that it is fine if you search etched bolt face.

http://www.snipershide.com/shooting/threads/pitted-bolt-face.31779/

 

[MarinePMI]

I took a harder look at my measurements and you’re right, I’m either just at the lands or slightly jammed. No more than 5 thousandths jammed if that’s the case.

Will call Tannel this week to get advice about my bolt face.

Greg will get you sorted out in short order...

 

[supercorndogs]

I took a harder look at my measurements and you’re right, I’m either just at the lands or slightly jammed. No more than 5 thousandths jammed if that’s the case.

Will call Tannel this week to get advice about my bolt face.

Just set the COAL at 2.8 for now. There should be a good spot probably around 42-42.7 in the heavier brass.

 

[CNJarvis]

Any chance that your bolt has a coating on it? The ridge looks like the primer, case contact has polished the bolt face and left a ridge of coating.?? I am not there, 2D picture and all, Ceracoate and such being common...

This is where my money is. If you look closely at the bolt face, you can see that the bolt has a coating on it, and that it has been worn off in places. Inside the recess, you can see that the coating has worn off exactly where the case head would be during firing.

 

[hotload]

This is where my money is. If you look closely at the bolt face, you can see that the bolt has a coating on it, and that it has been worn off in places. Inside the recess, you can see that the coating has worn off exactly where the case head would be during firing.

I like the outside the box thinking, but no. No coating on the BF. If you look at it under a hand lens, it looks like a micro torch cut a perfect circle rather than a raised surface where coating would be after everything around it wore off.

Spoke with Greg Tannel, his opinion (from the backstory and photo) is that its cosmetic damage only. Lesson learned. At least I caught it early. Also, I found the Primal Rights article on pressure to be extremely useful. Although aware of the importance of pressure and obvious signs of pressure like sticky bolt lift, cratered primers, s[lit necks, etc, I was not fully learned on how subtle the signs could be. It took a magnifying glass to really see them.

I was also surprised to see that there was a 17.5gr difference in the average weight of federal vs winchester brass, so appreciate that point from one comment above.