Follow up to neck tension thread

[mercervillerental]

Question - how hard do you push back on a seated bullet to make sure it has proper neck tension?

I had an issue (or maybe not?) with some new unfired LC brass that I’ve now been able to duplicate on new Starline brass and new JAG brass. Basically I’m able to push bullets back into the case with a bit of force, but now I’m wondering if I’m simply applying too much pressure.

I’ve tried numerous tests. Trimmed and untrimmed, chamfered and not chamfered, FLS with expander ball and FLS with no expander followed by a collet, and several combinations of the above (but not all) with a crimp applied with a Lee FCD.

At this point I’m pretty sure I’m simply pressing too hard on the brass but being 5’5 130lbs and not insanely strong I assumed it would be harder to do.

 

[Supersubes]

I don’t do that test ever. There’s no point. If you wanted to get all nerdy, test to see if they’re moving upon feeding into the chamber, or when the meplats bang into the front of the mag on recoil.

Ordinance brass is pretty consistent. We can calculate for desired neck tension, choose the proper equipment/techniques, and tune accordingly based downrange results.

 

[918v]

Take a factory round and try to seat the bullet deeper using your press. That’s the kind of feeling you want to duplicate. I like FGMM for this.

 

[spife7980]

You still haven’t provided us with one single measurement yet.

Measure your damn brass and see what’s going on for yourself.

And then report back to us with your findings.

Something like this, fired dimensions on the left, sized on the right.

 

[Steel head]

I don’t do that test ever. There’s no point. If you wanted to get all nerdy, test to see if they’re moving upon feeding into the chamber, or when the meplats bang into the front of the mag on recoil.

Ordinance brass is pretty consistent. We can calculate for desired neck tension, choose the proper equipment/techniques, and tune accordingly based downrange results.

This!!