Belt Damage??

[LambChoppa]

Hey all.

New to reloading belted mags. Haven’t spent much time around them so this may be nothing, but was looking for some input to what it might be and if it’s an issue. Tried the search but didn’t turn up much.

Shot some reloads today in a ladder test. I had a few cases show some wear/damage on the front edge of the belt. It’s like belt developed a bur or lip around the front edge. This occurred in cases with lower charge weights and some higher charge weights.

Federal Brass. It was all FL sized as it had been shot previously in 2 different chambers. This was only the 2nd firing on the brass. I know I don’t want to FL size all the time and over work the brass. Shot from Browning X Bolt.

Thanks much.

 

[918v]

Is your rifle shaving brass on new cases too or just these?

 

[LambChoppa]

It’s a buddies rifle. We shoot together often. I didn’t notice it on the brass he provided me. Only happened on 3 or 4 out of 25 reloads shot today.

 

[LambChoppa]

Also. After going back through the brass tonight I noticed 3 cases with a horizontal crack in the shoulder. One of which was from the starting charge and 2 from about 1 grain under book max. Velocity was right on par on the Xero so I’m confident in where I was.

Like I said this batch of brass (when factory loaded) had been shot in 2 different rifles prior to my FL size and reload so maybe these 3 got over worked?

 

[918v]

I think the brass is too big for the chamber.

Have your friend measure the brass before sizing and after. Compare those dimensions to the brass fired out of the rifle.

 

[LambChoppa]

I think the brass is too big for the chamber.

Have your friend measure the brass before sizing and after. Compare those dimensions to the brass fired out of the rifle.

I think the brass is too big for the chamber.

Have your friend measure the brass before sizing and after. Compare those dimensions to the brass fired out of the rifle.

I do all the loading for him. I suggested he buy a lot of brand new brass to start but he wanted to use what he had.

Are you thinking it’s too big for the chamber on the belt end and is causing the shaving on the belt? Or that’s what caused the cracks?

Everything was FL sized. When measured prior to and after sizing with a headspace comp the case head to shoulder moved several thousand back from the smallest piece I had. It was then trimmed, prep and loaded. I know with the FL it won’t change the base diameter and thats what I’m thinking is the issue with some pieces as far as the shaving goes.

 

[918v]

That’s what I’m thinking too. The base of the case is too big. The crack in the shoulder is a factory defect.

 

[LambChoppa]

That’s what I’m thinking too. The base of the case is too big. The crack in the shoulder is a factory defect.

With the belted mags everything just seems more critical. I’m thinking the ones shaving had first been fired in his other 7mag and the belts just expanded a little more.

Federal brass certainly doesn’t have a reputation for quality. A defect or just bad brass is likely on the shoulder cracks.

Thanks for the input!!!

 

[ZiaHunter]

Reloading belted cases is no different than non-belted cases in regards to setting headspace in the die. In both of my 300WM new cases will expand any where from .013 to .017 when fire formed. Set up the sizing die to set the shoulder back anywhere from .001 to .002. Sizing down to the belt will oversize and weaken the case with possible case failure. They was an excellent chapter in the Precision Reloading book that dealt with reloading belted cases but unfortunately it is out of print. Eventually the area just above the belt will expand and will result in tight chambering. The Larry Willis collet die will correct this. Unfortunately he passed away and not sure if they are still available. Over the years have loaded thousands of 300WM rounds and the only issue I have encountered is loose primer pockets after numerous firings.

 

[LambChoppa]

Thanks for the reply. That’s what I am shooting for moving forward. I always use the (controversial) shoulder bump per say. I use the Redding competition shell holders when needed or just have the die backed out a little. Some dies are easier to dial in than others and that’s when the Redding set comes in handy.

The brass I was using this time came from factory loads that had been shot in 2 different chambers so a true FL sizing was required. Moving forward that’s not the plan. Do you neck size, then FL size so many firings to help case life?

I have seen a lot of good reviews on the Larry Willis die. I had kicked around getting one but they are few and far between.

Also any input or thoughts on what may be causing the damage to the belt of the case, and the splits in the shoulder?