338 Edge brass from 7 RUM brass

buckbrush · #1 07-19-2009, 11:58 PM

Is that necking up too much?

Thanks.

Fiftydriver · #2 07-20-2009, 06:12 PM

The Rem brass generally has a very good anneal on the neck and shoulder and as such you will likely be able to do it but I would recommend annealing the neck of the case after stepping up to 30 cal just to be safe.

The necks will thin and you will have more clearance between the loaded round neck diameter and chamber neck but it would work.

If you do not anneal the case necks, you will likely see an increased percentage of neck splits on fired cases.

ZebDeming · #3 07-20-2009, 06:55 PM

My Edge brass was formed from 7mm RUM, only about 50 pieces, but it was all I could find at the time. I did have two case neck splits, and should have annealed the necks as Kirby said. That being said all I did was lube the inside of the neck and run it into a Lee .338 RUM sizing die. Some cases had some excessive neck runout and I think that could have been reduced by annealing and maybe necking to .30 before .338. It was my first time expanding brass and maybe it was just dumb luck

BTW the necks came out about .367-.366 od. I had to turn my necks as I have a .365 neck in my chamber. It was all Remington brass

Zeb

buckbrush · #4 07-22-2009, 11:45 AM

Thanks guys. I went ahead and tried it. Annealed first, then to .308 then to .338. The neck thickness didn't change more than 0.0005" on any of the six that I tried.

Looks like they will work.