380 ACP Brass Question

[LennieT]

I reload 38sp, 45ACP, and 9mm. Now and again one or two of the cases will split. Recently I started loading 380 ACP and am noticing what, to me, seems like and incredible number of split cases.

I purchase the 380 brass from a couple of different vendors. I picked out the ones that were obviously only fired once and put those up. I load the rest with 3.0 Bullseye and a Missouri 95 gr LRN bullet. I have not kept a real accurate count of split cases but it is running at more than 10%. I have also noticed that when other cases split they just have a split, while these 380 cases appear to be struck by lightening with a jagged split sometimes running all the way down to the base of the case.

Question, is 380 ACP brass extra thin or something. 3.0 Bullseye behind a 95 gr bullet measures a little over 800 fps on the chronograph. The splitting occurs in several different 380 guns. Thoughts?

Thanks
Lennie

 

[rcmodel]

Just bad brass most likely.

Nothing about the .380 ACP case makes it anymore susceptible to splitting then anything else.

The only other thing it could be caused by is an excessively small sizing die.
In which case, the brass is getting over-worked too much from sizing & expanding.

I do not believe that would cause any of it to split all the way to the base though.

That's just bad brass.

These are from one batch of Federal 9mm after being loaded once.




rc

 

[Claude Clay]

380 was 1 of the 1st 3 I reloaded ( 45 colt & 30-30 are the others)
in the intervening 52 years I have lost many more cases than have split

first guess would be to much belling -- if the splits are from the mouth down
if the splits are contained below the mouth than I'd like to know if this is related to one brand of brass more than another. than keep looking for commonality.
these are not steel or aluminum cases, yes?

3.0 & 95 gr is a mild factory load and splitting is uncommon...

 

[LennieT]

I will see what brands. I toss all the split brass in a bucket. I will pull the 380's out and see. The Federal brass above looks exactly like most of the 380 splits. Especially the ones where the split goes sideways across the brass. Thinking "bad brass."

Lennie

 

[MutinousDoug]

I wonder if your chamber isn't excessively oversize?

 

[LennieT]

Interesting, of the first 25 I picked out 20 were Federal, one CCI, two R-P, and two Speer. You can see in the picture that the split on some of this Federal brass does not start at the mouth of the case, so I am thinking it is bad brass.

 

[Potatohead]

I gotta think somethin aint right here. Did the brass come out of your great grandfathers underwear drawer, and then he passed it down to you or something? Just joshin but that's kind of weird.

 

[wlkjr]

Out of the more than 1000 I have loaded and shot, I have not had even one to look like these. I'm loading 3.1 Bullseye under a Berry 100g HBRN bullet and shooting mostly in two different Glock G42's. I have loaded other powders with the same bullet and shot in a Ruger LCP. I'd try shooting them in a different pistol just for reference.

 

[joustin]

I've got some 45 auto brass from 1971-73 that splits like that, not very common but it happens. I've had 223 do that too

 

[silverbullet86]

Are you sure you're not getting bullet setback (upon chambering) and spiking overpressure? I've had issues with .380 trying to get the bullets to stay put, even within correct size/resizing measurements.

Also, some newer Federal .380 brass has a "step" inside the case for just this reason. If you are seating a different (than factory) bullet length deep enough into the case, it could be putting pressure on that step?

Just some random different ideas...

 

[Walkalong]

That's just bad brass.

 

[medalguy]

Probably is bad brass but that's a lot. I'm still wondering why so much bad brass across a wide range of manufacturers. Could something have happened to the brass before the OP acquired it? Is this all brass you purchased?

I've probably loaded over 10,000 rounds of .380 over the past 5 years using 4.4 gr of AA #5 and never experienced a single split case as far as I can remember. Brass has mostly been range pickup with some purchased fired brass. That's a lot of .380 but it's my daughter's favorite.

 

[gamestalker]

I've been loading full tilt handgun including 9mm, 38, .357, and .40 cal for a very long time, like the better part of 30 yrs., and although I have had the occasional 9mm or .40 cal. that developed a mouth split, I've never had total case failure occur like that more than once or twice. So, since you indicate this is once fired brass, multiple firearms involved, and at a rate of about 10% failure, it's sounding like you are experiencing a high pressure situation.

There are a couple things that can cause a high pressure spike with a rimless AL cartridge, that is not related to the powder charge.

Over crimping can cause the mouth to pinch in the throat, this can drive pressures up excessively high on a cartridge that head spaces on the mouth.

This brings me to my next question, do you experience more than say .1% mis-fires? If you are getting an unusual number of mis-fires, like say at least 1 or 2 or more of every 100 or so rounds reloaded, you might be over crimping? And of those that do fire, they may be getting the mouth pinched in the throat, thus causing pressure spikes.

The other possible cause not related to your powder charge, is set back. Have you checked your loaded cartridges for set back? Set back can elevate pressures excessively high, so high that it can definitely split cases, and even worse in some instances. In this respect, over crimping can also be attributed to weak neck tension. Measure a handful of loaded cartridges, then manually cycle them through your firearm, then measure them again to see if they have experienced set back.

Also, pull some loaded cartridges and check the powder charges. It's possible that your powder measure is malfunctioning, or maybe your scale isn't delivering what you think it is? Check both.

GS

 

[LiveLife]

Since cases split with 3.0 gr loads, I would test 2.8/2.6/2.4 gr and see if they also split cases.

If they don't, I would use the powder charge that produce best accuracy.

What's your OAL/COL?

 

[1KPerDay]

The split ones aren't primarily nickel, are they? I've only had maybe 6 or 8 split cases in all calibers so far but most have been nickel.

 

[David4516]

I've been using 3.2gr of bullseye with 100gr FMJ and Rainier "plated" bullets, with the cheapest brass I could find (found lying around on the range, also some used brass on Ebay of unknown origin) as well as new brass (Starline).

I've shot maybe 500 or so between my wife and I (she has Glock 42, I have Makarov converted recently from 9X18 to .380ACP). No split cases but I did have a couple that looked bulged (not sure why I think they were fired in the Makarov, maybe the conversion barrel I got was bad?).

 

[Mad Chemist]

The OP stated 3.0gr Bullseye with a MBC 95gr lead bullet that is actually a pretty hot .380 load.

I think this is a combo of weak brass and a hot load.

 

[LennieT]

Mad Chemist, I am in agreement with you.
It is not an out of spec chamber because this happened with five different guns (LCP's and M&P 380's).

No misfires and I am using Wolf primers.
OAL .964 to .970
Not over crimped. Finished rounds match the specs in the Hornady manual and drop in my Wilson gauge the way you would expect them to.
Not bullett set back. Racked several rounds about a dozen time and measured each time. OAL was the except same before, during and after. Only did this in one of the guns, but that was the gun I used last time at the range and it had a bunch of split cases.
Powder measure not malfunctioning, I spot check about every 30 rounds and the charge is on the money every time with Bullseye. Also, use a lock-out die, but I realize that with Bullseye is does not take much to create a problem.

One other thing, all the split cases, regardless of brand look like the brass in the bottom half of the picture, or worse. That is making me think that I purchased a batch of brass with a bunch of really old brass mixed in.

Here is what I am going to do. From the same batch of brass I will load up 50 in what appear to be cases what have been fired only one or two times (top picture) and also load 50 in brass that has been fired, well, let's say way more than two times (bottom picture). I will keep them separate and see which group produced split cases.

I was using the 3.0 Bullseye because that was the starting load for 95 gr RN in the Hornady manual. After this test I am going to come off that 3.0 a little. I am betting that the old nasty brass will split and the newer will not. Will post after I get to the range this Weekend.

 

[lauderdale]

Maybe your scale isn't delivering what you think? as stated? I reedited as lenny T.s post came before mine. I think it would have to be bad brass.

 

[1KPerDay]

You may have said, but what pistol? Maybe your chamber is generous. You're not running them through a Makarov are you?

 

[rcmodel]

High pressure doesn't cause brass to split like that.

It can only expand so far to fit the chamber, no matter how high the pressure is.
And if it is elastic like it should be, it will expand to fit the chamber and not split or crack.

That brass will split just the same at low pressure as high pressure.
It is bad brass.

Perhaps someone cleaned it with ammonia or something before you got hold of it?

rc

 

[Rule3]

I do not have a problem with split brass. I either crush it in the press or the ones I do load and shoot end up in another County or black hole never to be found again.

I also think you have weak brass, chemically treated maybe?

 

[Blue68f100]

Some of those brass in the picture have the shoulder to prevent bullet setback. So these will have a smaller case volume, aka higher pressure. But I since those are heavier all I dought they will split.

Over the years you will run across batches of brass that just fails way before it's time. It's probably related to metallurgy of the brass. If the zinc has been leached out by chemical cleaning with an ammonia will cause this too. Inter-granular corrosion is another cause.

 

[gamestalker]

Yep, they might have had the zinc leached by improper cleaning? And considering the origin is mostly unknown, who knows how they were handled, or how many times they've been loaded, and the type of loads.

GS