Cartridge Case Head Separation
Cartridge Case Head Separation
This is a problem that can arise with multiple reloadings. I have been watching out for it with my 223 Rem cases. I figured the normally robust little cases would develop this sooner or later because I have been full-length resizing them and they have seen a few hot loads as well.
This situation has come about because of the number of review rifles in 223 Rem that I have worked with over the last few years. It is nigh on impossible to keep all the cases separated and, in the end, it was easier just to full-length resize every case.
What you need to look out for is the bright, thin line around the case about 5mm (1/4 inch) above the extraction groove on the case head. That fine, bright line is the tell-tale sign of the case wall thinning at that location. The photo shows three stages of development of this problem, from the faintest line to a shell that has cut right through nearly all the way around (it was a minor miracle that this shell did not separate!).
You can make a highly effective tool to detect that. All it requires is a paper clip, preferably one of the larger size variety. I actually made mine from a short length of nickel wire, after my paper clip tool went rusty. I also filed a little chisel edge on the point in order to pick up the faintest beginnings of thinning and crack development. However, that is nit really necessary; the blunt end of a bent paperclip will work fine.
It takes no more than a second to check a cartridge case. Having inserted the bent probe into the case I move it in and out three or four times as I rotate the case in my fingers. This effectively checks the entire inner surface of the shell. Any cases that have visible and/or probe detected thinning go into the bin. There is no fixing them. The last thing you want is a full separation of the case. When that happens, the front part of the shell remains wedged tightly in the chamber while the extractor yanks out the separated base.
This is hard enough to fix at home in the workshop, let alone out in the bush on a hunt. The key lesson here is to always clean and inspect your fired cases before reloading.
Good article, but isn’t case separation a sign of headspace issues rather than brass or reloading?
Hi Phil
Headspacing issues can cause case separations quite quickly.
Repeated reloading of brass for a variety of chamberings can lead to it in time, as well.
The 223 Rem brass I showed in the photo had been used repeatedly over about 15 years in at least half a dozen different rifles. I was not always scrupulous about adjusting the FLS die appropriately, either.
In my journey with reloading one episode taught me a lot.
I had acquired a new double rifle in 9.3x74R. I ran a few packets of factory ammo through it with no problems.
When I started to reload, I occasionally had a round that was really tight to chamber, in the top barrel only. Keep in mind that with doubles, the barrel that fires the first shot does the bulk of the shooting.
Soon I had a case head separation, which left the remnants of a case in the chamber of the second barrel. Luckily, I was able to extract it myself as I was at the time living in a very remote place.
It took me some time to work out what the problem was. It was so obvious in hindsight – a real d’uh! moment – but I was relatively inexperienced at the time.
The barrels on my double had significantly different headspacing, with the bottom barrel a longer headspace.
The odd case fired in the bottom barrel was very difficult to chamber in the top barrel and reloaded cases that had been fired in the top barrel were a bit short in the bottom barrel.
A double rifle is,essentially, two rifles welded together, so that should not have been such a revelation to me. I sort of knew that, but figured the manufacturer would have made both barrels identical. For a rifle designed to fire factory ammo and discard the cases, I guess it did not matter.
cheers
Don