I found a good deal on new 8mm Remington Magnum brass and can get them alot cheaper than the standard STW brass. My question is have any of you noticed any differnece in brass life when resizing from 8mm RM to the STW. What about 30-06 to 25-06 or anything else in that same area. Anything other than having to trim them after sizing them?

Thanks
Big-un

You should be able to do it but, make sure you don't put too much lube on the necks or you'll dent the shoulders. You're taking them down about .040" and that is a considerable amount in one pass but should be OK. To prevent sticking the case in the die, make sure you lube the base as well. This applies to all cartridge conversions, some are just more difficult than others depending on how radical a difference there is from the parent case to the one desired.

Compressing the neck brass that much may lead to premature neck splitting down the road. Annealing would eliminate the problem. If you are set up to anneal brass I would do that after resizing; before if you start to have problems resizing.

If you don't anneal don't worry. They will work, maybe just not for as many reloadings.

I use 8mm mag brass for my 7mm STW because I built my 7mm STW when it was still a wildcat and went ahead and bought 500 pieces of brass. I'm supposing the guys at Jensens in Tucson chambered my rifle accoprdingly because I've never had any problems. I've never had any problems necking the brass down and I've never felt the need to trim the neck thickness since the rifle has always been more accurate the I can hold. If the price is that good, I say go for it.

I have been shooting the 7mmstw since 1990 and have used 8mm brass for many years.It is a simple single pass through the 7mmstw sizing die with no problems at all.However you do need to trim the brass after the first firing.I have had no problems with necks splitting

I've been shooting 7MM STW since it was a Wildcat back in 1989. All my cases were made from 8MM Mag. Just run it through your regular 7mm stw sizing die. I used Imperial Die Sizing wax just a dab. That stuff works great. I load my STW right on top and I don't have any problems with my cases.

Thanks for the info guys, I just bought a Sendero in 7mm STW and have been tinkering around with it for a while. Anything else that would be helpful to know while loading this cartridge?

Thanks
Big-un

quote:

Anything else that would be helpful to know while loading this cartridge?

Thanks
Big-un

Yeah: There's no such thing as powder that is too slow. I've had the best luck with surplus WC-872 (in the lots I have, it is similar to WC-860 in burning speed but seems to provide better velocities and accuracy). Save powders like 7828 and RL-22 for "varmint" weight bullets. You can get WC-872 from several powder dealers, including Jeff Bartlett. Start with the "maximum" (a meaningless, but often used term) recommendations for H-870 and work up from there. Surplus powders tend to vary in burining speed, so my quoting you my loads might be misleading. At any rate, use your chronograph (if you don't have one, don't bother reloading for high-performance cartridges), watch pressure signs, and don't be tricked into believing that you can outdo a plain old 7mm RMag by all that much, perhaps a hundred or hundred-fifty FPS, depending on the length of your barrel and how hard you pull the trigger.

The above comments seem to have covered everything. No problems with 8mmRemMag brass to 7STW, slow powders, etc.
Using an Oehler chronograph to check load years ago when I first got my 7STW (right after first article came out), I found that the writer's loads were over maximum in my rifle. Later found his loads were over maximum in MOST rifles. Brass never lasted more than the second loading before primer pockets were enlarged.
Each rifle is a rule unto itself, but that also applies to each gunwriter's typewriter.

I use 80gr of imr-7828 behind a 140gr bullet in my rifles.The resulting velocity is right around 3500fps.The original loads published in the shooting times called for 83gr of imr-7828 which would certainly be too hot for my rifles.My own 7mmremmags produced 3200fps with their 24" barrels so my 7mmstws are producing 300fps more with their 26" barrels.With 26" barrels on the 7mmremmags the gap would close to around 200fps.