Need some help with some dies

[RussWatson]

Hi guys,

Need some help, just about to send my dies to Forster to get the necks honed for my first 6mm BR. Ive got a .268 chamber and wanted to try 0.002 neck tension to start, with 0.002 clearance. Am I right in thinking I need the necks of my die honed to 0.2625 to allow for 0.0015 spring back (Lapua brass) which leaves me 0.264" external neck dia. and 0.002" neck tension left?

Cheers

Russ

 

[SDDasher]

I think how often you anneal your brass will have an effect on the spring back as well.I use a O.264 ti bushing on my 0.268 neck Dasher to achieve the desired tension of 0.0015. The thickness of the neck wall is also a determination of the tension. Depending on what dimension you turn the necks.Again I turn necks to 0.011 and anneal after each firing.YMMV

 

[RussWatson]

Oh, hadn't thought about that! Assuming that 0.0015 is the spring back I'm getting, would my above calcs be right?