I am reloading for my Savage 12FV in .308Win.

After my first reloading session I got amazing groups with 180SMK at 100yr, best being .301" - three shots.

However I find the brass at the neck to be to thin (Winchester) against the neck of the chamber. It is .344" !

My question is,
who makes the thickest neck brass?

Lapua, Norma or maybe domestic brass maker?

Greeting

Peter

Hmmm ...
I think if I got 1/3 minute of angle groups on my first attempt with any gun, I would not be loking for thicker neck brass. I would be trying to find as much virgin, or once fired, brass of that lot as I could find!

Well, Peter, the problem is not that the necks of your brass are too thin, it's that your chamber's neck is to generous. This is common in factory chambers (along with maximum headspace and generally "fat" chamber bodies). The reason is that manufacturers want anybody's ammunition to fall into the chamber, and don't want any ammunition a consumer picks up to either chamber with difficulty or not chamber at all. Therefore -- they make big chambers.

Attempting to acquire or make brass with thicker necks to offset this oversized chamber is frought with difficulties. First, nobody's factory .308 brass is going to be thick enough to make a snug fit. Second, if you neck down and trim some larger caliber (like .30-06) you're also likely to have some uneveness in the neck wall thickness, which will hurt, rather than help, accuracy. You could turn the necks to make the neck walls even, but then they would once again be thinner than you might ideally like.

The best solution (and with near .3 minute groups you're already nearly there) is to size your necks down the minimum amount needed to secure the bullet. Lee Collet dies usually do a good job of this. Bushing-type neck sizing dies can also be set up to do minimal sizing.

You can try sizing only the top 3/4 or so of the neck. That will leave the bottom portion expanded so it holds the cartridge centered in the chamber.

If you form 308 from Federal 30-06 you will not encounter any unevenness in the neck. I form 22-250 from Federal 243 Win brass and have a perfect fit weith less than .002" runout every time.

Neck down a 35

quote:

Originally posted by Ralph Hyrlik:
If you form 308 from Federal 30-06 you will not encounter any unevenness in the neck. I form 22-250 from Federal 243 Win brass and have a perfect fit weith less than .002" runout every time.

Ralph: I agree on .243 from .308 (and have done it many times), but when forming .308 from .30-06 the former shoulder crease of the '06 case becomes part of the neck of the new .308 case. This can and often does create some uneveness. I haven't formed .22-250 from .243, but have formed it from .250 Savage, which works fine.

At any rate, attempting to manufacture better-fitting cases for a rifle that is already performing at or near its potential is probably misspent time and effort.

Same on the 22-250 from 243.

I decided to form my 22-250 brass because my chamber measures .258" at the neck and accepts brass as long as 1.930". With formed brass, I can keep 40 grain bullets .010" off the lands with half the bullet shank sitting in the throat. I have perfect alignment and the brass lasts for ever.

Thanks,
I tell you what I have done.
First, after fire forming my Winchester brass and trying different loads I couldn't believe how much those necks have opened.

When i messured it was .344" WOW
I like to use Wilson dies and only neck size, but I couldn't because it 'botle neck' the brass neck due to only partial neck resizing with wilson's bushing size .330, .331 was to loose.
So I pulled my Lee Collet Neck Die and I sized all neck, which is .328-1/2 - .329, and then I went again with wilson bushing .330 just to open the neck a bit.

Monday i will fire this brass second time and will find out more.

Peter

These are very nice groups. If you form your brass and leave only .001" clearance in the neck, then you won't have to size at all. The neck will spring back to original size. I have several cases that are past 30 reloads. The only sizing they need is to bump the shoulder back when the load is too hot.