Case expansion

[Steve12385]

Just wondering if anyone can help me with this. I have a walther ppk 380 and noticed that the brass is splitting almost 3/4 down the length of the case. I have tried 3 different brands of ammo. I would guess 1 out of 20 split and the other 19 are are pretty black as if the case isnt expanding enough and the gases are going around it. The ones that are split come out fairly clean. I marked the bullets in the chamber and they always split in the exact same spot, on the right side of the gun. I also measured the ammo diameter of unfired cases and fired cases of all my hanguns and all of them are a few thousandths bigger after being fired but the walther here is 10 thousands bigger. So im just wondering if anyone could tell me what is causing this ? Thanks for the help

Steve

 

[GLOOB]

The chamber is too big?. Probably cut out of round, too, since they're all splitting on the same side.

I suppose you've examined the chamber for cracks/bulges?

 

[tightgroup tiger]

^ What he said, I'd be looking for a new barrel.

 

[Miked7762]

The slide is opening far too soon and the cases are being blown out while still under high pressure. The splits in the cases are being started at the extractor cutout on the barrel since that is the first unsupported area the cases will encounter. If you look at your picture you'll see the discolored and bulged spot where this is happening. The recoil spring needs to be replaced.

 

[Steve12385]

Thanks for the input. Im gonna start with the easiest option so i ordered a coulpe recoil springs. A 20# one which is the factory standard and i also ordered a 24# one to see if it makes any difference. Thanks again

 

[Jim K]

Those look like some .380's I have seen that were fired in a PP Super.

Is the PPK a new gun (from S&W) or an older Walther or Interarms gun? If an S&W gun, return it to Walther USA. If it is an older gun, you can buy a new barrel, but it won't be cheap.

Jim

 

[Safetychain]

I've been having the same problem with my first reloads from back in the early 90's, only worse. I've been having a 75% split rate. After having brought the problem up here a year or so ago, I was convinced that it was maybe my inexperienced reloading, maybe flaring my cases too much. It was happening in a wartime Husqvarna, a new Khar, A new Keltec, and a new LCP. If it were just the old Husqvarna, I would agree with the possible spring solution. Or if it were just one particular gun, then it being a spring or too large a cylinder. I did not notice that the splitting was at the place where the unsupported portion of the case is (where the bulge is) but I will check on that next time out. But with it happening in all guns I tried, I feel it has to be ammunition related. Next time at a range, pick up some various brass from the ground and see if you agree that next to 22's, 380 has the thinnest case walls than any ammo out there. I would guess that in addition to my possible reloading mistakes, a tiny bit of work hardening of an already incredibly thin case wall will result in these cracks.

I haven't pursued the problem any further as I have decided to just shoot up the remaining few thousand rounds I have already reloaded before going to the bench again. I've still got about 20,000 pieces of 380 brass from that first bunch and have bought several thousand Berrys bullets from places and times when prices were really low.

Next time I may try some different trials before reloading all available bullets which is my usual practice. Some possibilities include greatly reducing or eliminating the case flairs and annealing some cases, and since my original 380 dies sat in my garage for over 5 years and have rusted up a bit, maybe polish the resizing die out a few thousands. It has the carbide ring but I have the jeweler's rouge and diamond abrasives that I use to resharpen my carbide bits and tools.

Please let us know what you determine to be the solution to your problem