OAL Norma 6 br and Lapua blue box

[Curmudgeon]

Morning, is there a difference in overall case length, once fire formed, between Norma 6 br brass and Lapua blue box brass? I see some threads with brass length over 1.5 but my formed blue box is less than 1.5. Thanks

 

[dmoran]

Most all the Blue box Lapua 6mmBR brass that I have measured typically are 1.553 to 1.555, with the bulk measuring 1.554". Most all the Norma 6mmBR brass that I have measured typically are 1.549 to 1.552, with the bulk measuring 1.551-ish. Any amount of forming/stretching to chamber walls, can rub length of the over-all. How much is dependent on the chamber size, headspace, and forming procedures.
Donovan

 

[Curmudgeon]

Thanks, am I to understand the case will diminish in length to accomodate the increased body length? I read case length of some shooters remains in the 1.5+ zone. I used the dasher reamer sold on Bullets, not the new reamer being offered. I remain slightly confused. Thanks for looking.