6.5 case split

[blackd24]

Loaded with once fired S&B brass (purchased online), Federal LR primer, Barnes 140 grain bullet and just above min charge of hybrid 100v based on the Barnes data. Weak brass? Any idea what happened here? There was a very small amount of smoke, but recoil was not different from my other rounds. I weigh every charge on a scale. I let the barrel cool down and shot a group of 3 and zero was spot on, accuracy was the same.

 

[AJC1]

You should have you chamber checked for gas cutting based on the lowest edge of the case. You may now have a small pit that causes extraction issues. If a buddy has a bore cam that would work.

 

[blackd24]

Not sure if it matters, but I’m shooting from a bolt rifle and did not have extraction issues from the 3 I fired after the case split.

 

[Blue68f100]

That's a major blow out for a crack. I would definitely take a look at the chamber looking for pitting caused by gas cutting.

Looks like it had a very thin spot possibly a pit. I would inspect the rest of the batch, it may be from some bad ammo that was torn down due to powder degrading.

 

[Bcwitt]

Did you have any other indications on the rest of your brass from same lot?

 

[AJC1]

Not sure if it matters, but I’m shooting from a bolt rifle and did not have extraction issues from the 3 I fired after the case split.

It's not the end of the world but if you have damage to your firearm, you should definitely know. I have a pit on my bolt face.

 

[Bcwitt]

Mabey saw that case in 2 & see if the case core was off center. If so I'd toss all that brass. You might want to pull down the rest of that lot.

 

[blackd24]

This came from a once fired mix lot online. All of the S&B appeared to have pretty rough rims which I assume means that may have been fired from an AR10. Another S&B case chambered, but the bolt would not close down on the round. I tossed that round, and i think it was because of the rim. I only had about 25 cases of S&B, but I plan on tossing them. My biggest concern would be damage to the rifle.

 

[AJC1]

This came from a once fired mix lot online. All of the S&B appeared to have pretty rough rims which I assume means that may have been fired from an AR10. Another S&B case chambered, but the bolt would not close down on the round. I tossed that round, and i think it was because of the rim. I only had about 25 cases of S&B, but I plan on tossing them. My biggest concern would be damage to the rifle.

On a side note recycling brass may help fund your reloading. Keeping cases in a recycling bin has proved to be very useful. Need a case to sacrifice to an annealing setup. Want to practice drilling and tapping a case for a hornaday tool. Besides when you get a full 5 gallon bucket of may buy you a pound of powder or a box of bullets.....

 

[edwardware]

That low in the case, I call it a defect in the brass prior to case forming. They are quite rare in general, but not unheard of.

In my experience, forming anything from HXP M2 brass will show ~5% cracks like that. Otherwise very rare.

I'll bet you have a smudge in your chamber, and further that it will never matter unless it keeps you up at night.

 

[Bcwitt]

The S&B brass I have used was very hard w a very high zinc content. Mabey it's just a defective case.

 

[AK Hunter]

How many times was that case loaded? It happens is why I try to keep my reloads down to 10 cycles, then I toss the brass.

 

[Hooda Thunkit]

I agree with @Bcwitt; could just be a defective case.

Sometimes brass does that. I've had cases crack for no apparent reason. Internal inconsistency, a defect in the alloy, a weak spot. Who knows? Toss it and forget it.

Unless it happens again.

 

[Charlie98]

I've had .308 cases do that on the 2nd or 3rd firing... I just think it's brittle brass. I'm not necessarily a big fan of S&B brass anyway,

This came from a once fired mix lot online.

Since my brass issues in .308 with some 'once fired' brass, I very rarely buy anyone else's once fired rifle brass, let alone mystery meat mix master brass... and particularly in a high pressure cartridge like 6.5CM.

 

[243winxb]

https://castboolits.gunloads.com/showthread.php?400716-6-5-CM-S-amp-B-Brass-issues

Looking like bad brass from the manufacturer.

 

[Charlie98]

I had some Winchester military brass neck crack on the 2nd loading... not a hot load at all. It was so consistent, I put it down to a hard lot...



I've also had a specific headstamp crack similar to the OP, but not quite as lengthy... again, I suspect a hard or poor lot of brass...

Edit: the corrosion you see is not from the brass... the brass got wet after firing.