Norma vs. Lapua 6BR brass

[OldSchool]

I saw an add on benchrest.com for a rifle in 6BR with the chamber cut for Norma brass instead of Lapua. Is there a big difference causing them to not be interchangable?

 

[GermanS1]

There's no practical difference in the brass. The correct designation for today's 6BR throated for longer bullets,105 class) is 6mm Norma BR, even Lapua brass is headstamped in this manner. This distiguishes it from the old Remington 6BR chambering which had a smaller base and shorter throat.