Home Forums Reloading Big Game Rifles forming 338-06 brass

I have read mixed versions of doing this. Anything from forming a false shoulder and fireforming to annealing and sizing up to just lube it and size it. I tend to go simple, and want to join the "lube and size" group. I have 30-06 brass, about 100 pcs of 2x fired rem and 100 of the 2x fired Nosler. I am thinking the Nosler will form easier as it seems softer when I work with it. Any problems I should be aware of/ looking for? and if I have it right it will simply be necked up with no changes to the shoulder? So I should be able to screw the expander ball below the die body and just run it over that and shoot? Seems simple. I do plan on hitting it with Hornady one shot before I run it through. Will it make a big difference if I chamfer the inside of the case mouth first, or is it not necessary? Like I said it seems simple enough, hopefully it works well. I did gave my gunsmith check the headspace with his 30-06 go/no go gauges and he said it looks fine.
I ordered some of the Speer 200 grain hot core, and have plenty of Win 748, Ramshot Big Game, and IMR 4350. I think I should be able to find something it will digest!

Maybe not so simple. It will depend on how the body/shoulder portion of the 30-06 chamber that fired the brass compares to the corresponding part of the 338-06 chamber. It's the same situation that occurs when you try to use neck sized brass from one chamber in a different chamber even though they're both for the same cartridge.

You could try just running the brass through 8mm then 338 sizers. If you’re lucky the shoulder will be right. If there’s too much head space there’s several options. A few include sizing to 35 and then back to 338 to get a crush fit or jamming the bullets into the rifling and shooting a less than maximum load and if your rifle has controlled feed you could perform the COW method.
Some don’t like the COW method because the “cream of wheat” is somewhat abrasive.

I’ve each of these methods. They all have +/- issues. If you have the proper dies or if you could borrow the dies running it to 35 Whelen and back down to 338-06 might be best (least expensive). If you use this method, you might want to anneal the brass.

He could just put a larger expander in the 338-06 die for the expansion stroke.

My die set for the cartridge is from RCBS. It can with a tampered expander ball...

The way I do it, is to anneal shot 30/06 brass.
De Prime with a universal deprimer.

The I run it thru the F/L die, with the expander ball & stem ran as high as it will go in the die...

that is how I do any of my sizing. regardless of caliber if I don't have a neck sizer only die... which is usually a Lee Neck Sizer..

with the Lee Neck Sizer, I then bump the shoulder back if needed with a body die...

Who messed with it?

I wasn't going to look a gift horse in the mouth on that one... I don't recall calling them and asking for one...
I bought it new... our it was supposedly " new"...

Trust your gut about keeping it simple. Just run your 30-06 brass through the 338-06 Die and load them. Realize that due to expanding from .308 to .338 your overall length is going to be shorter.

After you've fired them, re adjust your die to where the 338-06 brass will chamber without excessive sizing.

Done. Everyone is entitled to their own opinion but, there's lots of people over thinking the wheels off of it too.

If your worried, start with fresh virgin 30-06 brass.

Also, 4064, and H380 are your friends in the 338-06. Lots of good powders but those 2 are some of the best.

I use once fired 30-06 brass,lube inside of the necks well,light coat of lube on the body as usual,one trip through the 338-06 dies,brass a little short but not an issue.With 200gr bullets,my rifle really likes Big Game,but it also does well with any powder between Varget and 4350 burnrate.


200gr Accubond 59.0grs Big Game

I run spent 30-06 brass through the sizing die and load it. SO far, I have not had any issue with the neck being to short or case splitting. I have attached an example. Left is NEW Weatherby brass and right is couple times used 30-06 resized ( just lube and size ) to 338-06 from my RCBS dies.

In the 3 or 4 years I have had my 338-06 I have never had original brass. Right from the start I ran 06 brass thru the rcbs 338-06 die. Haven't had a problem that wasn't caused by me. Have been using some RP 270 brass also.

I've been using either new .35 Whelen or .30-06 brass for 20 years with no issues.
Just lube the neck and run it through.
It doesn't have to be rocket science.

Will be doing similar with .308 brass when my new .338 Fed gets here.

I'm probably the least experienced responder to this question. My experience is limited to reforming 60 once fired Hornady .308W. brass to .358W.

I tried to make it as simple as possible. I lubed the cases and inside the necks with Imperial sizing die wax and ran the cases through the .358 full length sizing die. The cases formed properly with no split necks. Ran them through the tumbler to clean the lube and loaded them.

They worked with no problems. I would have no problem making a large batch of brass using this method.

What everyone else has said so far.

Have had zero issues just running 30-06 brass through the 338-06 die.

This. One of the simplest "wildcats" (now, semi-wildcat) to load for.

30-06 brass, lube, run through die, using a bigger single stage, like a Rock Chucker, instead of a Partner helps.
Good luck

I’ve done 30/06, 270 and 35 Whelan brass. Anneal, lube, resize, check for splits or crack, done.