Split Brass

[Cornhusker]

Yesterday I was testing out some new loads in my 38-55, when I had two of the ten shells exhibit small splits about a quarter of an inch up from the rim.  I was wondering how many reloads should I expect for black powder loads before I discard a case?  Has anyone else had this experience with black powder loads?  I am using Winchester brass, 40 gr. Pyrodex P, Winchester large rifle primers, and the Lyman 378674 bullet.

[John Boy]

Has anyone else had this experience with black powder loads?

Never.  Cornhusker, how many times were these split cases reloaded and do you full length resize your brass aka full length these cases before you shot them?
Also, what rifle were they shot in?

I separate my brass by rifle and only neck size when I change a bullet for a given rifle and then use a neck expander to provide 0.001 to 0.002 neck tension.  And this is for Starline - Winchester and R-P brass.  Accordingly, all the cases are fireformed to the chamber in the rifle they are shot from

I have brass that has been reloaded 10+ times and even rim splits are rare with cases that are annealed and not

[Cornhusker]

I do full length resize, and the brass had been reloaded about five times.  The rifle is an H&R Target model.  I'll start just neck sizing and see how it goes.  The brass is some old Winchester factory loads that I pulled the bullets out of, so no telling how old the brass is.  I appreciate your input. 

[Lead pot]

If your getting case separation at that point the first thing I would check is the head space.
A straight walled case will last a very long time if they are cared for properly.
I have a rifle that has been shot 10K plus times using black powder with the same 400 cases over 8 years.
If your using black powder and dont wash your cases out, that will cause separation if you leave powder residue in the case for the powder to grab and pull the brass,

LP

[Cornhusker]

That is what I call excellent case life, lead pot!  I do wash my cases with soapy water and let air dry.  About every third reload I'll tumble my brass as well.  But, I must be doing something that is negatively affecting my brass life.  I hope it is the full length resizing that is working the brass too much.  I'll update this post once I run a couple of trials with just neck sizing the brass.

[John Traveler]

If by "splits" you mean annular cracks around the case near the rim, or a partial head separation, that is caused by a headspace problem or too many reloads.

If you mean that the "splits are lengthwise to the case, it is almost certainly a brass quality problem.  Case splits like this are relatively rare, but manufacturing defects do happen, and this is one sign of them.

[Cornhusker]

The cracks are along the length of the case.  Maybe the cases are defective?  I'm polishing the cases tonight and will examine them closely for defects.

[Ray Newman]

You said the brass was from some "old factory loads." How "old" is "old". That could be the major part of the problem. If it was happening to me, I'd buy new brass--esp. since 20% fail during a shooting session. That deosn't bode well for the remaining cases. I'd also have the headspace checked, but I never cared for shooting brass not knowing its age.....

As for case life w/ BP, a properly cared for case will last a long time. I once read in a re-print of Sharps catalogue that claimed the Sharps factory cases can be re-reloaded in excess of 500 times.

@ the start of the next Spring's shooting session, I only took one case to the range w/ pre-measured powder charges (BP, Duplex, or some White/nitro powder) & reloaded the Sharps . 45-2.4" @ the range. @ the end of ea. shooting session, the case was thoroughly washed & scrubbed, then polished in a tumbler. Every now & then, I annealed the neck. On the 538th firing, the case developed a split @ the neck & the primer pocket was just starting to get loose.

[Lead pot]

I had a problem with some .45/3.25 Bertram brass that split the length of the case that started around the forth loading.
What I did with that stuff after three split cases was throwing them in the scrap brass bucket.

Lp

[John Traveler]

The splits you described running the length of the case definitely indicate a brass problem.

I once had occasion to fireform some fired .348 Winchester cases that came from loaded cartridges made in the late 1940s to early 1950s.  After neck annealing and loading with caseforming charges and Cream of Wheat filler, they blew out nicely to .50 Swedish.   Loaded with black powder and 500 grain bullets and fired.  Many of them split near the casehead, with 1/4" long slits as you described.  Most of the rest split the same way on the second firing.  I never did get more than 2 or 3 loads out of those cases.  A metallurgist friend described how brass alloys tend to weaken with age, and that the splits showed accumulated stress where the .348 Winchester tapered case body was blown out to straightwall .50 Swede configuration.  Each firing further stresses the case to the point that it fails.

This same metallurgist described how brass alloys age and weaken (embrittlement) as they age, unlike ferrous alloys.  The example he gave was antique auto headlamps made 100 years ago from sheet brass, and how they commonly crack from age.  40 or 50 years aging of brass cartridge cases can make them unsuited for hot loads, whereas a steel gun barrel made 150 years ago is still as strong as it was when new.

[John Traveler]

Oh, yeah, I almost forgot.  Faulty brass is not necessarily old.

My active duty ordnance type friends in the Canadian Army described batches ("lots") of issued 5.56 NATO ammunition failing when first fired in combat in Afghanistan in early 2002.  Investigation showed the cases developd lengthwise splits when fired in the service rifles and SAW.  Coalition forces including US and Canadian units expeienced this, and the subsequent investigation showed inadequate manufacturer's heat treat quality control was the cause.