Thread: Increasing case neck tension

Hi team,

Came across a big issue on my latest hunting trip this weekend.

A number of my handloaded 7mm rem mag rounds which had been in a 20rnd ammo case had slid upward and hit the lid of the plastic case, resulting in the projectile being pushed beyond its set seating depth!

A number also did this when feeding from the magazine.

When I got home I found I could pull the projectile with some decent pressure using my fingers on 60% of the loads. Grrrrr.

Anyway I'm using a Lee neck sizing die with a lee classic press. I didn't have this issue when the brass was fresh, but now that it has been shot once this issue is appearing. It is something I have not come across this before.

Anyone have any recommendations for increasing neck tension so that this doesn't happen. I don't really want to have to crimp them.

Cheers team.

Throw your neck die away and use a full length sizer, then live happily ever after

Originally Posted by dannyb

Throw your neck die away and use a full length sizer, then live happily ever after

Set up correctly to bump the shoulder 2 thou or so

rduce the diameter of the expander ball...2 minute job with cordless drill and fine sand paper.

Sounds like a collet die. Good when working, frustrating when not…

I just full length size nowadays but as above measure shoulder bump to avoid oversizing

Cheers for the advice fellas. Had a bit of a fiddle around before and I believe I have got it working so it is sizing properly just at the full extent of the lever pull. The projectile sits firmly on top of the case and can't be forced in at all as before. Did two presses om opposite sides of the case as per the lee instructions which seems to have helped a bit also. Fingers crossed I can keep it consistent. We will find out tomorrow.

Another learning curve!

is it a collet die

Anneal and throw away your expander. Heresy but it bloody works. FLS.

Sure is.

I think Lee say something like 50lb on the press handle. How do you judge that evrevery y time? So I just set my collet dies so the press cams over and of course do the 2 sides thing. This gives repeatable consistant neck tension.

I'll just leave this here

https://youtu.be/lLG2kSrD40g?si=2_0S_l2HXV91ucqg

Eric Cortina vid now not trademe add

an add for trademe????? weird.....or is that weirdo??? lol

Greetings,
I have seen this problem over and over again with the Lee Collet dies and the problem is always brass that is too hard. You need to anneal the necks after each third load max and better more frequently. The Collet dies produce very straight necks, which aid accuracy but do need brass that is not too hard. The die is not the problem it is the hard brass.
Regards Grandpamac.

If I read OP correctly he is either on 1x reloaded or 2x reloaded.

One way to test the effectiveness of collet dies is to test using the die mandrel ie remove die from press and slip case over the mandrel and gauge "sloppiness'. There will always be a degree due to springback but as GPM states after several sizings the brass will spring back more so and the fit of the mandrel into the neck will be noticeable more loose.

Originally Posted by Micky Duck

an add for trademe????? weird.....or is that weirdo??? lol

Weird Allright have fixed now....dunno what happened there