Lapua neck thickness

[ASbobcat]

Just bought some new Lapua brass that has been professionally turned to a thickness of .012 and I was very happy to find it. I will tell you why.

Several years ago, during the last 6BR brass panic, I scrounged several partial boxes of Gold and to my dismay every lot had a different neck thickness. So I picked the thinnest, which turned out to be .012 and turned all the thicker ones down to match the least common denominator. I immediately noticed that seating force became far more consistent and ACCURACY IMPROVED!

That was pure serendipity. Turning down necks got a bad rap from some of the early PPC shooters who shaved their necks paper thin. They got great accuracy. but paid the price in reduced brass life. I talked to some who had to repeat that very laborious process at the start of every season.

The real eye opener came with some blue box I bought earlier this year. Even with virgin, factory annealed necks after expanding with a mandrel, the seating force was so great it left deep rings in my ogives! No more .0135 for me!

So I'm passing on my lucky discovery, that .012 thickness just happens to be the sweet spot for the 6BR, improving accuracy without sacrificing brass life.

Having spent hours and days neck turning and uniforming primer pockets, I can tell you it's well worth paying someone else to do it. I have reloaders elbow to prove it.

Contact "sportpsyc" for ifo. He is great to deal with, and has a good stock of this brass.

 

[Straightshooter1]

Just bought some new Lapua brass that has been professionally turned to a thickness of .012 and I was very happy to find it. I will tell you why.

Several years ago, during the last 6BR brass panic, I scrounged several partial boxes of Gold and to my dismay every lot had a different neck thickness. So I picked the thinnest, which turned out to be .012 and turned all the thicker ones down to match the least common denominator. I immediately noticed that seating force became far more consistent and ACCURACY IMPROVED!

That was pure serendipity. Turning down necks got a bad rap from some of the early PPC shooters who shaved their necks paper thin. They got great accuracy. but paid the price in reduced brass life. I talked to some who had to repeat that very laborious process at the start of every season.

The real eye opener came with some blue box I bought earlier this year. Even with virgin, factory annealed necks after expanding with a mandrel, the seating force was so great it left deep rings in my ogives! No more .0135 for me!

So I'm passing on my lucky discovery, that .012 thickness just happens to be the sweet spot for the 6BR, improving accuracy without sacrificing brass life.

Having spent hours and days neck turning and uniforming primer pockets, I can tell you it's well worth paying someone else to do it. I have reloaders elbow to prove it.

Contact "sportpsyc" for ifo. He is great to deal with, and has a good stock of this brass.

I take it you have a no-turn chamber? If so, how much clearance would you say your chamber has after turning to .012"?

 

[JEFFPPC]

Your correct in that consistency in most things has value. As a long time thin neck guy I will disagree on thin necks reducing case life. Squeezing every last fps from the PPC case and killing the primer pockets is why we go thru so much brass. To me clearance is clearance. I have never seen any definitive testing on this amount of clearance is better than that amount. I have made errors and turned brass too thin, it would still tune as good as what I considered correct, You hit the gold ring with the value of consistency. Why we measure bullets, weigh powder to one piece, weigh brass etc. The biggest consistency most miss developing loads at shooting matches is simple......wind. But most hate flags. How do guys put value in their testing without knowing they are shooting CONSISTENTLY in the same condition.

 

[Clancy]

.2683 or less in a .272 chamber has consistently shot the best for me across the board. Even if you don’t turn, the added clearance flat out shoots better. I do see less seating force variation in turned brass, but I don’t see a difference on target as long as I have a minimum of .0035 total clearance.

 

[mjl650]

I take it you have a no-turn chamber? If so, how much clearance would you say your chamber has after turning to .012"?

I just started turning my Lapua necks in a 6BRA to .012”(in reality to between .0120” & .0122”) for a no turn .272 neck. With the 105 Hybrid loaded round I’m getting .2678” to .2680”. So there’s .004”+ clearance.
I’m happy with the results on the target.

 

[ASbobcat]

I take it you have a no-turn chamber? If so, how much clearance would you say your chamber has after turning to .012"?

My chamber is .271 NO-TURN.

There is a common misconception that tight necks improve accuracy. The ONLY thing a tight neck does is improve brass life, because of less work hardening in the neck.

The cartridge is aligned at the front by the FREEBORE, which in almost all bolt action chambers is caliber plus .0005in.

You cannot have a neck clearance that tight because it would not allow the bullet to release safely. That's why the neck clearance has NO effect on accuracy.

 

[ASbobcat]

I just started turning my Lapua necks in a 6BRA to .012”(in reality to between .0120” & .0122”) for a no turn .272 neck. With the 105 Hybrid loaded round I’m getting .2678” to .2680”. So there’s .004”+ clearance.
I’m happy with the results on the target.

Another convert. You have learned well Grasshopper.