6BR & neck tension

[JFrank]

Closer to.0035 or .003 with springback and whether or not you anneal. Resizing from the outside springs back to outside. Resizing with mandrel / ball springs back to inside. On paper .004. Bushings spring out.

I’ve never been able to document spring back of the neck OD, meaning I can size a piece of brass with a .262 bushing and the neck will remain .262, where is the spring back ?

 

[6BRA]

pin guages...are the only sure way to tell...especially if you arent turning necks.

 

[JFrank]

pin guages...are the only sure way to tell...especially if you arent turning necks.

I am turning necks and I’m sure that I’m reading the tool correctly. Still no spring back, it doesn’t matter really, I just wouldn’t factor it into any bullet hold or neck sizing considerations.
J

 

[Dave M.]

That’s basically identical to what I’m running on my 6BRA.

Very close to what I’m running too

 

[Dave M.]

I am turning necks and I’m sure that I’m reading the tool correctly. Still no spring back, it doesn’t matter really, I just wouldn’t factor it into any bullet hold or neck sizing considerations.
J

No spring back on brass is a sign of over annealing brass. Essentially, you have turned the brass into a “dead” material similar to lead. One partial solution to this phenomenon is to significantly increase neck “tension” and allow the hoop stress of the brass hold the round. This is the down side to annealing brass. Brass can withstand a fair amount of over annealing before going dead. I’d like more details as to what led up to the brass not having any spring back.
Dave

 

[Dave M.]

I’m now running a .265 bushing on a .268 neck.

I’m running a .265 Redding bushing on one of dashers with a .2685 loaded neck. And the other is using a .266 SAC bushing on a .2695 loaded neck. Both rifles have a .272 no turn neck chamber.

 

[JFrank]

No spring back on brass is a sign of over annealing brass. Essentially, you have turned the brass into a “dead” material similar to lead. One partial solution to this phenomenon is to significantly increase neck “tension” and allow the hoop stress of the brass hold the round. This is the down side to annealing brass. Brass can withstand a fair amount of over annealing before going dead. I’d like more details as to what led up to the brass not having any spring back.
Dave

I don’t anneal brass either.
Here’s some once fired bass i sized probably two weeks ago with a .261 bushing, what I’m suggesting is that of all the 99 other things we stress about spring back would number 98 on the list.

 

[Dave M.]

I don’t anneal brass either.
Here’s some once fired bass i sized probably two weeks ago with a .261 bushing, what I’m suggesting is that of all the 99 other things we stress about spring back would number 98 on the list.

Don’t trust the sizes labeled on the bushings. Get some pin gages and measure them.

 

[Bill Norris]

Don’t trust the sizes labeled on the bushings. Get some pin gages and measure them.

Some will not be as labeled.

 

[Ruger15151]

Short Action Customs (SAC) neck bushings and Bullet Central Micron neck bushings are the best I have ever used. The induce almost no runout and are very true to size.

 

[JFrank]

Don’t trust the sizes labeled on the bushings. Get some pin gages and measure them.

Well, I always varify the ID but when they are stamped .261 and size .261, what’s the need for pin gauges ?
I’m not trying to be argumentative, I’m just saying IMO there are bigger knobs to turn when looking for performance.

 

[Dave M.]

Well, I always varify the ID but when they are stamped .261 and size .261, what’s the need for pin gauges ?
I’m not trying to be argumentative, I’m just saying IMO there are bigger knobs to turn when looking for performance.

True true. I was merely saying that unless you truly measure the bushing with pin gages, you could very well have a bushing that measures .2605 and then it is springing back to .261

 

[Dave M.]

Short Action Customs (SAC) neck bushings and Bullet Central Micron neck bushings are the best I have ever used. The induce almost no runout and are very true to size.

I can’t speak to the BC micron ones, but the SAC bushings are the best I’ve ever used.

 

[Dave M.]

Some will not be as labeled.

100% TRUE SIR