Author Topic: Trimmed undersized brass cases (Read 541 times)

savageT · « **on:** November 25, 2004, 05:10:06 PM »

On a couple occasions, I have overtrimmed a few brass cases when trimming 6.5x55mm back (about 10/1000ths). I know reloading overlength cases is supposed to be a No-No, but what about undersized cases? With my Swedish Mauser chamber, I get allot of case stretching and wondered what the critical dimensions were really all about (plus and minus)

?

Jim

KYsquirrelsniper · « **Reply #1 on:** November 25, 2004, 07:39:06 PM »

Loading overtrimmed (too short) cases usually won't cause any problems, and it usually won't create any dangerous situations. The worst case scenerio (which is unlikely) is if you trim the cases way too short, to the point where you no longer have enough neck tension to hold the bullet firmly in place, the seating depth may be altered due to feeding or moving around in the magazine under recoil. In the usual instances of overtrimming just a few thousandths, about the only thing that will happen is that there may be a slight loss of accuracy, but most times you'll never be able to notice it.

Siskiyou · « **Reply #2 on:** November 25, 2004, 08:13:33 PM »

Savage T: I resize 06 cases into .270 win cases all the time. They come out a little short and I have had not problem with them.

Reed1911 · « **Reply #3 on:** November 26, 2004, 01:42:18 AM »

I agree. You should not have any problems provided this is a one time event. If you continue to over trim them, your brass life will suffer a bit.

savageT · « **Reply #4 on:** November 26, 2004, 02:42:31 AM »

Thanks for your information.
In the past when I've overtrimmed, I crush the case and throw the "shorty" into the recycle bag.
If you don't mind, please explain to me what hapens when a case is out of specs...either too long or too short? Since the bottlenecks are registered on the shoulder, is the biggest danger (in the case of too long) is dangerous high pressures?

Jim

Reed1911 · « **Reply #5 on:** November 26, 2004, 03:13:44 AM »

Too long of a case will be a problem depending on how the chamber is cut. If it's long throated you proably won't notice a hard chambering problem, but once the brass moves beyond it's relief cut; when fired it holds too much tension on the bullet and pressure rises dramatically. Even a medium load will show excessive pressure signs in this event. If the chamber has been cut short, an overlength case might exibit failure to chamber to hard to chamber events.

savageT · « **Reply #6 on:** November 26, 2004, 03:18:23 AM »

Thanks again Ron!

Jim

Siskiyou · « **Reply #7 on:** November 26, 2004, 08:38:37 AM »

Back in my early teenage days I learned a little less about pressure. I had loaded a number of cases 4 or 5 times. About the fifth time I started to get sticky extraction and a little primer flow. Every thing appeared the same as far as bullet, primer, powder type and charge. I bought a case gauge. The cases had grown well out of maximum trim length. My next purchase was a case trimmer.

I have had no pressure problems with short cases.