6BR Measurement to Datum Line

[zedsdead]

Getting ready to put my 6BR Savage together and going over everything. Just measuring new Lapua brass and with a Stoney Point gauge I am getting 1.158-1.159 from case head to datum line. I'm going to run the brass through a full length sizer here shortly and wondering if I should set the die up to bump the shoulder or just hit the necks? I checked the diagram on the 6BR page and did not see a measurement for the datum line.

Jason

 

[Cheechako]

Jason

Is the headspace on the BR Norma measured to a true datum line? My C.I.P. drawing does not show such a measurement.

Does Stoney Point make a claim that their guage measures to an established datum line?

Either way, I don't think I'd be FL sizing and pushing shoulders around until I have the actual rifle in hand to gauge just how much sizing needed to be done. I know that a new rifle is exciting and you're anxious to get things done ASAP but sometimes it's better to bite the bullet and wait to do things in their turn.

JMHO

Ray

 

[expiper]

I hope this is resized correctly...Roger

 

[fdshuster]

Jason: Except for verifying that the case neck is round & not dented, load & fire the new brass 'as-issued' out of the box. It will fire form to your individual chamber dimensions, minus approx. .001' of spring back. Then, take a headspace length measurement with the Stoney Point/Hornady gage, record that number for future reference, as when/if adjusting the sizing die. The makers of the various gages cannot give you any meaningful headspace length dimensions, since it will vary with each chamber, the brass used, and the gage used. When having a new chamber cut, one of the first cases fired is decapped with a hand punch, polished & kept with that barrel, for the life of the barrel, and all dimensions are written & kept with the die set. Same dimensions are recorded & kept as they relate to throat depth with all the bullets used in that chambering. A lot of record keeping, I know, but it has proven beneficial to me, many times over.

 

[RJinTexas]

Jason, Frank has given you some very sound advice. That's absolutely the best way to do it. I just wish I'd have been as diligent in keeping records, it would have sure save me a lot of time in the reloading room over the years.

RJ