New barrel issue

[Grillnugz]

Got a new barrel chambered by a gunsmith. After firing there is a ring or bulge about 1/4-1/3 of the way down past the shoulder. See photo below of a fired pice of brass to the left and virgin to the right:


This bulge is very apparent when examining the fired brass both visually and by feel.

Below is an image of a fired (left) and resized (right) pieces of brass. The budge is still there. Resizing took more force than normal and extra lube. Additional note the scratches in the shoulder area. These scratches are the same for every piece of brass that’s been chambered.


The resized brass measures the same length as virgin brass, however when I try to chamber the resized brass the bolt is very difficult to close. All brass is .01-.015 below the maximum case length. With the FL sizing die set to cam over (maximum sizing) the shoulder grew + 0.002”.

The barrel shot ok, but I just started load development so too early to tell.

Has anyone experienced bulges in their brass like this? Are these scratches acceptable? The chamber job seems sloppy, what’s the best was to get something like this resolved? Since the brass is bulging out, I’m not sure cleaning up the chamber will fix the issue.

 

[BBob]

Well he hooked a chip in the reamer and ringed the chamber now didn’t he??? No way to fix it other than run the reamer deeper till it goes away and re-do the tenon. Was it setup for the barrel to match a specific stock inlet?

 

[huntnful]

Had the exact same thing happen before. It'll need a new chamber. I was lucky that mine was basically a straight shank barrel. So he just cut 1" off and rechambered.

 

[Grillnugz]

The stock’s barrel channel is wide, probably could fit an M24 contour. The barrel is a sendero contour. Is reworking possible with this contour or is the shank too short?

Any ideas on what is causing the chambering issues with 1x fired resized brass?

 

[huntnful]

The stock’s barrel channel is wide, probably could fit an M24 contour. The barrel is a sendero contour. Is reworking possible with this contour or is the shank too short?

Any ideas on what is causing the chambering issues with 1x fired resized brass?

Idk if the shank can be reworked. It depends how deep he'd have to go with the reamer to hit a spot wide enough to remove that gouge.

As far as the resized brass not fitting, you're saying you have the press and die set correctly, but your shoulder is growing .002 after FL sizing. That's not correct. You NEED to set the die deep enough to bump the shoulder. Preferably -.002

 

[Grillnugz]

I’ve had some tikkas where the shoulder wouldn’t bump the first firing or two. I’d experience .001-.003” in shoulder growth when sizing. The full length dies in all cases (rcbs and Hornady) were set to cam over (maximum allowed sizing). But the resized brass would chamber no problem. I think die manufacturers error on the side of less shoulder bump as it reduces the chance of over sizing and splitting cases.


These dies are new so it’s possible they were cut long. Since it’s a prc rifle I’d expect bump after the first sizing given the “tight” chamber specs.

I appreciate the input, looks like a trip back to the smith is needed, ugh.

 

[Ucsdryder]

Had a chamber that did that. A different gunsmith cleaned it up. I think he polished the chamber? Maybe he ran a reamer through it. I can’t remember now, but the “gunsmith” that did the initial chambering left the chamber rough which caused the rings. Mine had multiple.

 

[wyosam]

If you don’t have the shank to go deeper, maybe a fatter cartridge would clean it up. I don’t know magnum bolt face cartridges well, is the WSM or SAUM any bigger than the PRC case? Sherman have anything?


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[huntnful]

I’ve had some tikkas where the shoulder wouldn’t bump the first firing or two. I’d experience .001-.003” in shoulder growth when sizing. The full length dies in all cases (rcbs and Hornady) were set to cam over (maximum allowed sizing). But the resized brass would chamber no problem. I think die manufacturers error on the side of less shoulder bump as it reduces the chance of over sizing and splitting cases.


These dies are new so it’s possible they were cut long. Since it’s a prc rifle I’d expect bump after the first sizing given the “tight” chamber specs.

I appreciate the input, looks like a trip back to the smith is needed, ugh.

Disregard the whole cam over "maximum allowed sizing" stuff. Screw the die in, until it bumps the shoulder. That's how you size a piece of brass. Not by a random pull stroke feeling, which is variable, between two surfaces that have sub par consistency to mate to each other at all when coming off the shelf from different manufacturers (shell holder & sizing die).

I'm just letting you know that it's not correct, and how to do it correctly. If you have shoulder bump comparators, use them and bump the shoulders.

 

[Grillnugz]

Disregard the whole cam over "maximum allowed sizing" stuff. Screw the die in, until it bumps the shoulder. That's how you size a piece of brass. Not by a random pull stroke feeling, which is variable, between two surfaces that have sub par consistency to mate to each other at all when coming off the shelf from different manufacturers (shell holder & sizing die).

I'm just letting you know that it's not correct, and how to do it correctly. If you have shoulder bump comparators, use them and bump the shoulders.

Good call, those die instructions suck. Got plenty of bump just now following your wisdom. Thanks!

Took a good 1/2-3/4 turn past normal die setup instructions.

 

[huntnful]

Good call, those die instructions suck. Got plenty of bump just now following your wisdom. Thanks!

Took a good 1/2-3/4 turn past normal die setup instructions.

Good to hear! It should chamber fine now. Or at least decently, because that wide spot in your chamber is going to cause issues with chambering and extracting indefinitely. But at least your shoulder won’t be bound up when you go to close the bolt now.

 

[vonb]

I have one that does that on the shoulder. Gunsmith offered a free barrel job on next re-barrel. I left it as is on current barrel and just shoot it. The barrel is a hammer. Over time, the mark in the brass has become less pronounced. I’d just run as is unless it’s causing problems.

 

[wind gypsy]

If you don’t have the shank to go deeper, maybe a fatter cartridge would clean it up. I don’t know magnum bolt face cartridges well, is the WSM or SAUM any bigger than the PRC case? Sherman have anything?

Yes, saum and wsm are rebated rim cartridges with the same case head size but fatter in web.

 

[Wrench]

You can likely sink the reamer another thread or two and clean it up.....but how is the case width at .200" up from the head? If the chamber is oversized you'll work the snot out of your brass and get short life. If it's just a hung chip.....that's an easy fix.