Bushing starting size for 6.5 PRC

B-LOT Banga

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I've recently received my first "bushing" die set from Hornady and I was searching for a good starting size for my 6.5 PRC using 140 Berger hybrid and ADG brass. They dies came without bushings so I'm lost as where to start. Any help would be greatly appreciated thanks in advance.

Aloha!!
 
The Forster 6.5 bushing bump dies comes with three Bushings in dia. .274″, .272″, .270″
This should help, but your neck thickness and uniformity is the deciding factor. Normally you measure the neck diameter of a loaded round and subtract .002 with neck turned brass. And if you do not neck turn and the neck thickness varies .002 or more you subtract .004 and use the expander. Also note that brass spring back after sizing will effect bushing size. Meaning brass that is not annealed gets harder each time it is reloaded and springs back more.

Tech Line & Tips (FAQs)
https://www.redding-reloading.com/tech-line-a-tips-faqs
 
Measure the case neck wall thickness and neck outside diameter, then decide what bushing will give you the neck tension, you desire. I usually get 3 sizes to cover most brass I use, for a .001 or .002 neck tension.
 
The Forster 6.5 bushing bump dies comes with three Bushings in dia. .274″, .272″, .270″
This should help, but your neck thickness and uniformity is the deciding factor. Normally you measure the neck diameter of a loaded round and subtract .002 with neck turned brass. And if you do not neck turn and the neck thickness varies .002 or more you subtract .004 and use the expander. Also note that brass spring back after sizing will effect bushing size. Meaning brass that is not annealed gets harder each time it is reloaded and springs back more.

Tech Line & Tips (FAQs)
https://www.redding-reloading.com/tech-line-a-tips-faqs

Thank you... I appreciate it.
 
I'm running .288 in my Hornady dies with Hornady brass. That's based on measuring a loaded round and emailing with Hornady. The post above seems like it's way too much neck tension, but maybe the ADG brass is more different than I thought. Forresters own data says .288-.292 is included with 6.5 dies. The numbers above in the .27 area are likely for 6mm. Proceed with caution...
 
I really appreciate everyone's reply. I actually measured a 260 rem, 6.5 CM and 26 Nosler just to see the ball park. After seeing the difference from the given spec I looked into it and seen it was for a 6mm. But I didn't want to say anything because I appreciate everyone's help and I caught it before ordering. Thanks again for your input!!

Aloha
 
The .289 for Hornady cases and .290 for ADG are the bushings I use to get the desired neck tension. A loaded round with a Berger 140 in ADG brass is .293
 
Measure YOUR components always. Too much variation between manufactures and lots. Good choice going with adg. Mine is very consistent

Joe
 
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The reason to get a few bushings is not to adjust tension. It's because bushing neck sizing of more than 4thou causes more than stamped on the bushing. Depending on your chamber, you may need to back off a thou or so.

Tension with partial neck sizing is ~1thou grip (max). Any more interference will just be resized back up by the seating bullet. The reason to go 2thou under cal is to set condition for expansion (bullet pre-seating). After expansion necks spring back inward, and will continue to try & relax inward, so tension does not weaken over time. Where you do not expand, spring back is outward, relaxing is outward, tension decreases over time.
 
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