Getting Started: 6mm BR Norma neck bushing question

[Webster]

I've decided to start shooting 6mm BR for short range benchrest. I have a beginner's question: How do I know what neck size bushing to order when I don't have factory ammo to compare to determine a size when ordering a neck bushing?

I've watched videos on prepping dies, but other than using a full length sizing die and ignoring neck sizing, I have no idea how to use a neck sizer that comes with a set I've ordered. Or rather, what determines good or bad neck tension.

Thanks for any help.

I ended up with 4 bushings. No turn chamber, Lapua cases, I turn to 0.0125" neck thickness and I always use my .265' bushing. Don't bother spending the money for TiC coated bushings. Buy regular steel and put some lube on the necks.

 

[Bill Clifton]

I'm pretty sure my 6br no turn neck die has a .266 in it. I run Lapua brass.

 

[Pareto]

I'm pretty sure my 6br no turn neck die has a .266 in it. I run Lapua brass.

I will try several because I've gotten answers from no-neck users that run from .266 to .268 so it is clearly both subjective and variable with respect to the gun and the shooter.

 

[Bill Norris]

I will try several because I've gotten answers from no-neck users that run from .266 to .268 so it is clearly both subjective and variable with respect to the gun and the shooter.

Wise decision to try more than one size.

 

[divingin]

By knowing the specs on the chamber or reamer.

No way of telling what reamer spec was used if it's a factory rifle.

In general, Lapua brass runs 13 to 14 thousandths a side. So 26 to 28 thou for brass, plus 243 for the bullet gives you 269 to 271, and you subtract a bit for springback, yielding 267 to 269. I run a 267 for no-turn at the moment. I started with a 268, as I recall.

You'll likely eventually end up with a few bushings; I'd go ahead and get several centered around where you're likely to be. A little extra money now is better than having to wait for a new bushing to arrive to be able to shoot.

 

[JSH]

No way of telling what reamer spec was used if it's a factory rifle.

In general, Lapua brass runs 13 to 14 thousandths a side. So 26 to 28 thou for brass, plus 243 for the bullet gives you 269 to 271, and you subtract a bit for springback, yielding 267 to 269. I run a 267 for no-turn at the moment. I started with a 268, as I recall.

You'll likely eventually end up with a few bushings; I'd go ahead and get several centered around where you're likely to be. A little extra money now is better than having to wait for a new bushing to arrive to be able to shoot.

And….cerosafe is your friend. A call to the factory would narrow things down. When one deals with wild cats/non SAMMI cartridges can be a big learning curve.

I will admit to buying a few “pigs in a poke” myself.

 

[bulaman]

I use a 0.267" in mine with Lapua Brass and a 0.272" no turn neck. So I also agree with 0.266"-0.268" bushings should cover you.