I'm out of 308win brass. I have some ordered.

Noticed I had a lot of 243 Win brass so decided to try and form 308 from 243. Just as an experiment. Not that I want do this on a big scale.

lubed the inside of the neck and ran through a 7mm-08 die then the 308 die.

It appears to be a 308 win case now. Length is right for a 308. Chambers in the gun just fine.

Question - Does any other operation need to be performed on this converted brass?

Is this brass safe to use as is?

Thanks

You will be close enough. Any small inconsistencies due to the resizing will be corrected on the first firing. I go this route with the 25/06 .270 and 3006 pretty often and have never had an issue.

Your necks may be uneven after forming or fireforming! You may have to trim them to even them up. I like to anneal when necking brass whether it is necking up or necking down.

Hip

it is a 308 case now.
it was a 30-08 case before it was a 6mm-08 case.
now it's back where it started only without the stamp on the bottom saying so.

fire form it, cut the case mouth straight, throw an anneal on it and carry on.

Grafs has a real good selection of .308 brass. I don't bother to neck up/down unless the real thing is non-existent or I'm making up a wildcat. Necking up always thins the neck walls and after you get it where ya' want, it needs to be annealed.

I have formed 7mm-08 brass from 308.

I have form 7mm-08 form 243 I found federal 243 worked the best.

I have now found enough 7mm-08 brass not to worry.

OP was asking about 308

I wouldn't expect it to last long. Annealing might help but that is a lot of stretching at the neck. Otherwise it should be fine.

quote:

Originally posted by john c.:
OP was asking about 308

Same concept.

quote:

Originally posted by Wstrnhuntr:
I wouldn't expect it to last long. Annealing might help but that is a lot of stretching at the neck. Otherwise it should be fine.

Annealing will definitely help! I am working the 20th. loading of my .375 H&H AI made from .300 WBY brass, 14 loadings of .338 WM made from 7mm RM and a bunch of loadings for my .375 Win. made from .30-30.

Yes annealing sure will help!

Try it, you don't have much to lose and you will learn from it.

Hip

quote:

Originally posted by p dog shooter:

quote:

Originally posted by john c.:
OP was asking about 308

Same concept.

except thread was about OPs interest. not yours. which has never bothered you before. just everyone else. short man "me me" complex.

Necking the case neck down or up: Be very sure you have neck clearance after seating a bullet. you may have to turn the outside of the neck. I have formed many 30/06 cases to 308 for benchrest type rifles. Because the barrels were machine gun barrels the chamber was a little loose for the cartridge, I tightened up the chamber neck with the formed 30/06 cases. And accuracy before forming the cases was very accurate. Out of all of the rifles the smith built the only complaint was from the shooter that purchased the rifle with a generous chamber.

And now I am wondering what kind of a problem he is having sizing those cases that were fired from a machine gun (barrel).

F. Guffey

quote:

Originally posted by john c.:

quote:

Originally posted by p dog shooter:

quote:

Originally posted by john c.:
OP was asking about 308

Same concept.

except thread was about OPs interest. not yours. which has never bothered you before. just everyone else. short man "me me" complex.

Experience in necking up cases is just that experience in necking up cases.

If the head size is the same, you can convert any case anything else.

Only thing you cannot do is make it longer.

Shorter is is always possible.

One of the most ridiculous case firming I have ever had to do is make brass for the 300 Phoenix.

An over rated cartridge which never made.

I had to make the brass from 338 Lapua magnum.

The Phoenix is also shorter.

As you can imagine, this involved several operations.

I was given the rifle by a friend who does not reload.

And there is no factory ammo.

quote:

Necking the case neck down or up:

Necking up and or down; It is assumed the neck of the case gets thicker and or thinner; No consideration is given for the possibility the case neck gets longer and or shorter when necking up and or down.

I have formed short cases with longer cases to offset generous chamber necks like the 308 W, 7.65 Nato machinegun barrels chamber.

F. Guffey