7 SAUM neck tension?

[kennyg]

I have a question for you experts out there. My 7 SAUM build is almost done, (finally) and I am trying to decide if I should send my Forster FL sizing die to Forster and have them hone the neck out a bit.

I removed the expander ball and sized a few fired cases. The sized necks measured .3105-.311. Loaded rounds with Berger 180s measure .315, which means that neck tension is .004-.0045. Is this too much?

The rifle will be a repeater, so I want enough neck tension to prevent bullet setback. How much neck tension are you 7 SAUM shooters running?

Thanks in advance for the help!

 

[243winxb]

The expander opens the neck up, as i am sure you know. The dies are not over working the brass. May be hard to seat a flat base bullet without using an expander. A neck tension of .002" is plenty. But brass springs back. Inward using an expander. Outward using a bushing or die with no expander. If your not going to use an expander, open the die up for less tension. (Not an expert & dont own a 7 SAUM)

 

[Gadget]

+1 for A neck tension of .002" it's plenty in most F Class guns,
I personally only run .001" in a single feed Barnard P, 7mm rsaum.
My loaded round is .315 and I use a .314 bush no expander ball, Redding F/L bushing die.
Gadget

 

[kennyg]

Okay, so I was thinking I would have the neck opened up .002, which would give me about .002-.0025 neck tension. I guess my question is, would this be worth it, or should I just use the expander ball to open the necks back up that .002. FYI the necks have been cleaned up about 90 % or so.

 

[ericskennard]

I would try it as is first. I find with the 7mm -284 and RSAUM that .003 is not out of line. Since you are going to use a repeater, you may want the tension.

I never use an expander ball on the dies but I do use bushing dies.

 

[RGRobinett]

I would try it as is first. I find with the 7mm -284 and RSAUM that .003 is not out of line. Since you are going to use a repeater, you may want the tension.

I never use an expander ball on the dies but I do use bushing dies.

Ditto that - and 0.004 isn't a wreck either. RG