Recommended neck tension for 6.5CM AR-10

[steves86ta]

Been doing some research and not finding to much. Gonna start loading some 'precisionish' ammo for my stag-10 in 6.5 creedmoor. I will shoot it in f-class but don't really plan to be to competitive. Just looking to have fun.

Currently loading 6.5cm with a standard Forster full length sizing die. I have not measured to know what I'm getting for neck tension but plan to later today

I used to load 6.5cm for a bolt gun and used a Wilson mandrel that gave me .0015 neck tension

I no longer have that die but am planning on getting a new system and want to use a 21st century mandrel. I know I will need more than the .0015 I used in the past but not sure what would be recommended for this being semi auto

I'm currently not having issues with setback or anything, and my SD and ES are what I would consider acceptable for the loading process I am using.

My current process is FL sizing, trimming, tumbling, chamfer, resize with one shot (to make sure necks are good), charging (using rcbs electronic powder drop) and then seating, and finally tumbling again to remove the one shot.

Id like to change the process just to change time and clean things up

Id like to change my process to FL size without button, trim, tumble, chamfer, then expand mandrel and load on a progressive.

I'm thinking maybe a mandrel that will give me somewhere around .003-.004 tension but wanted to ask here first.

Thank you

 

[Kracken McGraw]

If you don’t go that route you could always add a Lee Factory crimp die after seating, they are very easy to adjust.

 

[steves86ta]

If you don’t go that route you could always add a Lee Factory crimp die after seating, they are very easy to adjust.

Yeah I use one of these for my bulk 308 ammo.

Id rather not use one for the creedmoor stuff but might

 

[rlporter507]

I think you can only go so far with neck tension, at some point the bullet is just an expander mandrel. I have a 260 rem, and so far the bullet moves with .004 tension. if i lay it on the mag, they get longer. if I push them in the chamber, they get shorter. I load them .010 off, and lay them on the mag. Im thinking thats the most consistent, they'll stop when they hit the lands. the 10 is just a monster chambering rounds. shooting prone, its difficult for me to drop the bolt from halfway using the charge handle with a sling on. Mines even hard to push the bolt release.

 

[steves86ta]

If my math is right and my calipers fairly accurate it appears with the Forster die im getting right at .003" neck tension. If this is the case ill get a mandrel to give me about .003 and should be fine

Bullet - .264
Case thickness - .012
Loaded diameter - 0.291
Should come out to somewhere around .003