A buddy of mine just got his dad's old rifle and wants me to load up some ammo for him. Is this just a straight sizing of 338 mag cases through the 308 N.M. dies,do i have to fire form, or what?
thanks for any help.

I would have to look and see, I do think that you can form brass but I cannot remember what from.

did you know that it is only a wildcat from the standpoint that there is no factory available rifle chambered for it. Brass is available for both the 308 norma and 358 norma. It is pricey as it is only available from Norma. But really, it should last you a while.

The norma came first, there's no excuse for the 300win. :-)

Red

There is a little fire forming involved. You can run 338 brass into your 308 norma die and load and fire. The case headspaces on the rim. However the shoulder will move forward .045". So after the first firing you will gain some capacity. The neck will be shorter than factory. But, that will not cause a problem. The 308 norma holds about 91 grains of water. The 30-338 holds around 87. Nosler says you can use the loads for the 308 Norma in the 30-338. You could also buy factory cases.

Make cases from .300 Win Mag brass, not .338 Win mag!

Adjust your sizing die so that the new cases will just chamber -- you are thus headspacing on the shoulder rather than the belt (which varies more than it should!). You get zero case stretch above the web too.

The cases thus made are also longer so you will have the proper neck length too. Don't forget to trim!

jpb

Thanks I knew this was the place to ask,

jpb You got it. This is the way I have been making mine for about 20 yrs. Depending on the make of 300 Win brass you use you may have to anneal the shoulder area. Using this method I dont remember the last time I lost a case in the forming operation.

You can make the cases from just about any mag head brass. I personally use 338WM because you don't have to trim much.

You can still set the head space off the shoulder for the initail firing when using 338WM because the 338 neck diameter is bigger than the 308 neck diameter. Just set the die up to size as such.

I don't use 300WM because you do have to trim, and I had a number of instances of lube denting the necks on the newly formed .308 brass (yes too much lube). I don't have to deal with either when using 338. Just size, load and shoot.

Turok

The 300 is what I heard could be used. I guess I am lazy for buying the brass. I did get it for a good price, does that make a difference? :-)

Red

Sure Dago, a good deal makes all our sins seem small, lol. - Dan