Home Forums Hunting & Shooting Custom Rifles & Wildcats Making.308 Norma mag from 300WM

When sizing in a redding FL die the shoulder is crushed down just below the shoulder. Do I need more steps to form 308 norma mag brass?

You shouldn't; I do it in one pass in RCBS die. GD

In the past I used 338 WM brass. Very slightly shorter than the Norma but not enough to matter.

I'd use 338wm brass, myself..

Or else neck up 7mm RM brass

I don't use them because they are shorter by .050. If I want to use 338 or 7mm brass, I chamber a 30-338. GD

Making 308 Norma Magnum brass,I usually use 7mag brass because I have a lot of once fired brass.The max length on the 7mag brass is 2.50.The max on the 308 Norma Magnum is 2.56.The difference is about the thickness of a penny in the case neck length between the two cases.I tried making cases from 300 Win Mag cases.You have to totally push back and reform the shoulder of the brass and also trim afterwards.Since chambers are a little generous in the neck,I never noticed the shorter 7mag or 338 Win Mag cases run through the 308 Norma Magnum dies make a noticeable difference.Here is a picture of a full length brass case chambered in one of my 30-06 rifles.You can see there is a lot of room beyond the max case length to grow.I checked my 308 Norma Magnum rifles and they looked to have about the same amount of room with a full length 308 Norma Magnum case chambered.

For a hunting rifle, I'm a lot happier with .010 max clearance than .060. Cases form easily from 300. The trimming is more work than the sizing and it ain't much. GD

Thanks for all the info. can make it from 338WM but short, does anyone use a forming die or a two-step process for 300WM?

Thanks for all the info. can make it from 338WM but short, does anyone use a forming die or a two-step process for 300WM? The redding die does not have a vent hole, does that will make a difference?

Not having a vent can make a difference but usually not in this case. the cases are a similar shape and diameter so there is not enough air trapped to be a problem. Just be sure not to over lube the shoulder; the lube can cause dents. GD

Too bad you can't find factory 308 Norma brass.. I can understand the schidt is expensive, when you do find it, unless you get lucky and find it at a shop that doesn't know what it is worth.

I have Redding dies and it's quite an easy process making the brass with one pass.You won't tell any difference between in necking it down and just resizing a regular case,same with necking up once-fired 7mag cases.I think the die does have a vent hole under the nut.I do have Norma 308 Norma Magnum brass I bought from Bruno Shooters Supply,but I have to reduce my loads a little because that brass is a lot softer than Winchester or Remington brass.If I don't,my primer pockets can get loose after the first firing.I guess it's a good thing in a way,at least you know your pressure is OK.I've never had an issue with loose primer pockets an any brass other than the Norma.

Baldhunter - nice to see a 308 Norma Guy in the area, Rockport here. LOL

Looks like we a neighbors from across the bay!!!

i use RCBS dies without this problem. I do use Imperial sizing wax.

That is very true Baldhunter, I live on a canal to the bay LOL

I would be willing to trade 308 norma brass for 300 win mag brass. I was going to build a 308 norma had trouble finding a model 70 smith with a reamer and ended up with a 300 wm. So now I have some 308 norma I don’t need anymore.

The OP would probably take you up on that offer. That is very generous of you..

Not sure how generous I am being. I am pretty picky about my brass. 😂