Split Case From Max Load

[murf]

suggest you contact starline and tell them about this. it seems this batch of brass has not been annealed properly.

luck,

murf

 

[Legionnaire]

I can't honestly remember if I've shot any factory ammo. I've probably only put 100 rounds through this gun at most since I've had it. I feel like I may have shot a few factory rounds the first time I had it out, but I'm not positive. I did shoot some reloads with plated bullets and PPU brass that had been fired 3x and it all performed fine. They were loaded fairly light since they were plated bullets though. That's what makes me think it's not a gun issue, but I don't know that for sure.

I'd still take some measurements of your fired brass. Overpressure is likely, but that could be exacerbated by an oversized chamber.

 

[mdi]

"...it was new never fired Starline brass."

I'm not a metallurgist, but looking at the jagged split, it appears to be pretty "hard" brass. I think an over pressure split would be a "slit", a smooth sided opening. I have used brand new Starline brass for some 44 Magnum loads, even my "T-Rex" loads ( 265 gr cast bullet over max. loads of WC820) in my Puma carbine with no over pressure signs so I can't be of much help. Perhaps sending one case to Starline for an explanation?

 

[Riomouse911]

"...it was new never fired Starline brass."

I'm not a metallurgist, but looking at the jagged split, it appears to be pretty "hard" brass. I think an over pressure split would be a "slit", a smooth sided opening. I have used brand new Starline brass for some 44 Magnum loads, even my "T-Rex" loads ( 265 gr cast bullet over max. loads of WC820) in my Puma carbine with no over pressure signs so I can't be of much help. Perhaps sending one case to Starline for an explanation?

That looks exactly like the old-case splits I was describing. My cases were work hardened nickel ones that had 8-10 reloadings on them so I think you’re right about the bad cases being too hard from the get-go.

Stay safe.

 

[Charlie98]

I have some RP .41MAG brass that I bought new around 1992... 1000 of them... that I'm still using today. Even though it's almost 30 years old, most of it has survived. Some of it has probably been loaded 10x or more. Every once in a blue moon I'll get a case that splits like that, and I've seen it in other brass as well. I believe it's finally starting to work-harden. I might lose 1 case every 200-300 rounds with a split like the OP's.

I also have a 1000 case lot of Midway (Starline) .45ACP brass from the same era. About 10 years ago, I started getting case splits with it... brass that sees nowhere near the pressures some of my .41MAG loads produce, and the .45 cases have probably seen about as many loadings as my .41 brass; I was losing about 1 per 30-40 rounds. It's my theory that Starline brass is either harder from the start, or work-hardens faster. I have other .45 brass that is even older than my Midway brass... Federal, Speer, PMC, Winchester... that I know was abused... and, again, I rarely get case splits.

All that is in addition to the .38SPC and .357MAG cases that I had issues with, mentioned previously.

 

[Bill M.]

My first split cases came from a fairly heavy load (but near the starting load for that powder) and I was worried about it. But...I can not see how a max load can really stretch or stress the main body of the case more than a medium or light load. The case is thin brass and it expands to fit the chamber. Looks like 12,000 psi would be enough to do that and that 35,000 would not do more. I think the problem lies somehow with the brass rather than the load.