Gunsmithing Case head separated, damage??

[jackinfl]

I must have picked up a piece of 6.5 Creedmoor, with my 6mm Creedmoor brass. The 1 piece of 6.5 went through my reloading process.
Full length resizing, 39.2 of h4350, fgmm120m, 108 elements.

Anyway, the round fired. Nothing to note on recoil. Bolt lift was heavy. I had to hit it up and back. I felt the brass tear and pull off.

I tried to get the rest of the case out of the chamber. No luck. I don't want to scratch the chamber.

I spoke to my gunsmith. He said to pull the barrel and he'll Remove it.

This is on one of my Zermatt Origin actions.

My question or concern is the lug mark at 6:00 on the barrel. That is the extractor side on the Origin. I looked I did not see any damage to the bolt head.

I know I need to watch what brass I pick up.

Causes???
Was this brass reloaded several times? Or did I over throw powder?

I have thoroughly checked the rest of my loaded 6mm and prepped brass. All are 6mm.

Any input is appreciated.

Jack

 

[Powder_Burns]

For my 300wm rifle, I had a case head separate on the 8th firing. Made a tool to feel for grooves inside the brass just above the web. Its a piece of wire bent 90° with a sharp edge, as you run it down the inside wall of the case you can feel if there is a groove present or not, that indicates if the case wall is thinning above the web. Use a comparator to measure shoulder bump, try not to push the shoulder back more than .003 to minimize the brass stretching too much during firing.

 

[m1match]

I would think that its very unlikely that you caused any damage to your rifle. Besides checking your cases like @Powder_Burns said, check how much you were bumping your shoulders back. Every case head separation I have had has been because I didn't check how much I was bumping the shoulders back and adjusting my dies properly. One batch of 308 instead of bumping the shoulder .002"-.003" I was bumping them almost .010" and a case had a partial separation after only 3 firings. The only other time I had one was with my AR service rifle where I loaded a batch of cases probably 15 times and I wasn't checking the cases with a bent paper clip.

 

[sgtsmmiii]

Take a .30 caliber brass rifle brush - screw it into a pistol cleaning rod. Push the brush past the remaining case, and pull back. Should pop right out.

 

[DAVETOOLEY]

If the bore brush doesn't get it out I've used a tap the right size. I run it in until it just gets a bite on the case walls and then tap it out with a cleaning rod. Sounds scaring and it is the first time you do it. A 1/2" rat tail file works also. Carefully run it in and give it a twist to get a bite on the sidewalls. Then tap with cleaning rod. There maybe a carbon ring in the chamber. A quick polish with a Scotch Brite pad or 0000 steel wool takes care of it. Do it 20-30 times and you can etch the chamber.

 

[jackinfl]

Thanks for the suggestions. I tried over sized pistol brush with no luck. Mr. Tooley if you were closer I'd swing by and have you do it. My gunsmith is a 4 hour drive, the brown truck is going to do the drive this time. We have a Match next Saturday, if he gets it done I will grab it at the match. IF not, NO big deal.
I do need to figure out a process though because if it happens once...

 

[DAVETOOLEY]

When I was competing a lot there was always a file somewhere close for anyone to use. We taped up the body to protect the inside of the action. I used to have one in my cleaning kit but someone borrowed it and didn't bring it back. A 1/2" file works on all calibers except 223.

 

[jhunter]

I have had success using a 9mm brush to remove a separated case in a 6mm. Force it in past the case mouth and snatch it out.

 

[Brux]

I have used a case extractor.

 

[Tokay444]

High likely hood that brass was worn out before you ever picked it up, but that primer is really flat.

 

[JBoomhauer]

I have that mark on all my origin barrels.

 

[Yondering]

I would think that its very unlikely that you caused any damage to your rifle. Besides checking your cases like @Powder_Burns said, check how much you were bumping your shoulders back. Every case head separation I have had has been because I didn't check how much I was bumping the shoulders back and adjusting my dies properly. One batch of 308 instead of bumping the shoulder .002"-.003" I was bumping them almost .010" and a case had a partial separation after only 3 firings. The only other time I had one was with my AR service rifle where I loaded a batch of cases probably 15 times and I wasn't checking the cases with a bent paper clip.

This on all counts. Case head separations happen because of excess headspace. Using a 6.5 Creed case shouldn't have anything to do with it, except that maybe somebody else had been bumping shoulders too much already and that case was ready to go. 6.5 and 6mm Creed shoulder dimensions are the same and the simple neck down doesn't cause a case head separation.

I'd check the rest of your brass for impending separations. You can use a paperclip, but it's a lot simpler and more reliable to just look in the cases with a bright flashlight; you'll see a shadow ring near the case head if there's an impending separation issue. If in doubt, it's really worth doing this.

 

[FisherT&C]

Plug the chamber with end with cleaning patches and sit the barrel muzzle up in a coffee can or something similar. Pour some Hoppes #9 down the bore and prop the barrel up in the corner muzzle up for 24 hrs. The Hoppes has a small amount of ammonia in it and will slightly etch the case which will make it easier to remove. Your trying to get the Hoppes between the chamber wall and the brass. It's a slow chemical reaction so you have to wait 24 hrs.

 

[Jerry m]

Take a .30 caliber brass rifle brush - screw it into a pistol cleaning rod. Push the brush past the remaining case, and pull back. Should pop right out.

^This^. But if you have access to a freezer put the barrel in it overnight first.

Good luck

Jerry