6mmBr OAL length?

[Leere]

Hello,
I need some direction and understanding why?
I purchased a 6mm Br left hand feed single shot savage model 12 1:8 twist 26" barrel. Two of my friends and I checked OAL of a chambered cartridge touching the lands and that came out to 2.43, We prepared a 105gr A-Max bullet, Lapua case, rem 7.5 primer, 28gr Varget and set this cartridge OAL to 2.33. I believe that to be .010 from the lands for a starting point with this load. Here's my two questions. The previous owner told me he shot 58gr A-Max and 70gr Nossler ballistic tip bullets with the same Lapua cases I have that came with this rifle. He seated these shorter bullets so they were .010 from the lands. How can that be right? I would like to shoot the 58gr V-Max and 70gr Nossler bullets. What should I set the OAL for these bullets knowing my OAL for this rifle is 2.43, I'm GUESSING I will be at 2.23 for these loads and .020 from the lands.

 

[jelrod1]

You need to look at your decimals. You are changing, or talking about changing in .100 increments instead of .010. I would double check all of your measurements and be sure of them.

 

[Dave A]

Perhaps I am misunderstanding when you talk about OAL of a loaded cartridge, but the determinative factor is where the ogive of the bullet contacts the lands. This of course varies with different bullet designs and even within different lots of the same bullet from the same mfg.

 

[Leere]

Thanks for the advice, I have researched ogive which I never knew about. After researching ogive I have rechecked my measurements and change the way I view OAL.

 

[Dave A]

Your welcome and glad I could help out. There is a lot of experience in the people that post on these pages and a tremendous amount of information if you do a bit of reading in past postings.