Lapua 6BR flash hole size.

[Dave T]

I know this has been covered before but maybe there is some new info on this topic. I read the 6BR Cartridge Guide in Accurate Shooter and they recommend leaving the flash hole size alone and not reaming. Then it says that flash holes anywhere from .059" - .063" is normal, so am I going to ruin and compromise accuracy if I ream my 6BR Lapua flash holes to .0625? Oh and also chamfer the flash hole.
Dave T

 

[artbosco]

My 30BR uses the Lapua 6BR Norma as its parent. I used to open the flash hole up to .0625" then went to leaving them at .059". The only thing I've noticed is that I now have more time for something else. And, no measurable difference seen on target either.

 

[L-46]

Think that Jack Neary did some testing in a 100 yd tunnel with the 'best' PPC that they could assemble.
From memory the difference was not really noticeable, so he does not alter it now
L-46