Switching caliber, bolt head question?

[skoger]

If you change from a .308 to. 6BR, they use the same head size, 473 I believe , but isn't there 2 different primers for 6 BR, some large some small primer? Fixing to help a buddy, done a lot of builds, but no 6BR yet. All feedback appreciated !

[Hotolds442]

Primer cup size doesn't matter, both would use the same bolt head and firing pin.

[bootsmcguire]

Primer cup size doesn't matter, both would use the same bolt head and firing pin.

http://i747.photobucket.com/albums/xx111/bootsmcguire/ICONS%20and%20Forum%20Stuff/nail.gif (http://s747.photobucket.com/user/bootsmcguire/media/ICONS%20and%20Forum%20Stuff/nail.gif.html)

[GaCop]

All new 6mm Norma BR brass will be small rifle primer. The older Remington round used large rifle primers and had a shorter neck IIRC. The bolt head, as stated, is not affected.

[defoxer]

If 0.473 is 12.01mm then yes they are the same...as are the vast majority of standard cartridges, the Germans are a smidge smaller though at 11.95, and the Soviets/PPCs smaller still but should function without issue in the standard bolt-face

The 6mmBR Norma is different to the 6mmBR Rem, the Rem cartridge is a quarter inch shorter in over all length, case is near identical except for the rim with a slightly different chamfer...
Rem has bit more freebore and rifling leade is twice the angle of the Norma (3deg vs 1.5deg)