Need Help with 7MM WSM Neck Tension

[Elkbane]

I recently purchased a 7mmWSM and need some help managing neck tension. Here's the situation:

Using Winchester brass, I performed an initial turning just to clean up the necks a little before fireforming (neck wall variation was pretty bad, bordering horrendous). After fireforming, using a Forster F/L die , and after turning to 14.2 thousandth necks wall thickenss (I kept turning down until I got acceptable variation - still not totally consistent, but this is where I ended up), I'm getting neck O/D of .312 - .3125" (calipers).

Subtracting 14.2x2 from .312" = .2836" O/S, and sure enough 7mm bullets are almost a press fit inside the case. Amax 162 gr slide in pretty easily, Berger 168 gr have a little more tension, but neither have enought neck tension for a hunting rifle, which is the intended purpose. The expander ball in the die measures .2825" (calipers) and isn't even contacting the interior neck walls that I can tell.

Question: What would be the best way to further reduce the O/D of the neck? A Redding S type F/L die or a neck sizing die? I want as much of the neck sized as I can get since the 7mm WSM case has a pretty short neck to start with. I'm thinking my practice would probably be to F/L size, then post-process with a bushing die to gain neck tension. I guess I'm looking for a die that sizes as much of the neck as possible.

Any words of wisdom from someone who has faced this before? This is the forst time I've had a F/L die that didn't way oversize the neck....

Thanks,
Elkbane

 

[Zia Hunter]

Since you are turning the necks to a relatively consistent neck thickness, first try running the cases through the die without the expander plug to see if that helps. If not, you may want to consider going to a die such as a Redding Type S die with the appropriate bushing. There may also be a problem with the die itself and not properly reamed. A neck thickness of .0145 is still greater than most new unturned brass and most likely not the problem.

 

[RDavies]

The Redding bushing dies do seem to size nearly all the way down the neck. I remove the expander part of all dies and let the bushing do the sizing.

 

[Elkbane]

OK thanks guys. I ordered a Type S die with .312 and .311 titanuim bushings. Will give them a try in a few days.

I'm really liking the rifle so far - it's a Winchester M70 Extreme Weather SS with a Zeiss 4-14x44 scope for an all-weather hunting rifle. Fit and finish is good, the stock is well designed (stiff, with an aluminum insert) and the factory even made a passing attempt at bedding in the recoil lug and rear action screw areas. Trigger is decent after some adjustments. Recoil is not objectionable, but I'm not particularly recoil sensitive.

Elkbane