Neck turned too much?

[newmexkid]

OK. Today I did a very stupid(I think) thing. I had an appointment this afternoon at the V.A. and I decided I had time to neck turn some of my 25.06 Remington cases. Well, in my stupid haste I suddenly noticed that I seemed to be cleaning about 90-95% of the neck. Three of the cases cleaned up 100%. I had done 10 cases when I thought, "what in the h*** are you doing?! So...My beautifully turned cases are measuring at between 0.13 and .014. The cases that didn't clean up completely are measuring between 0.14 to 0.15. Are these cases ruined??

 

[AZShooter]

They are not ruined. But you may have a shorter brass life depending on your chamber dimensions. Many of us have turned brass down far more than that! I have a 30 BR that I turn down to .0105".


The issue isn't the amount of brass turned off but the dimension of the chamber neck vs the OD of a loaded round. There must be some space for bullet release. In some cases the reamer was made with a custom tight neck which required turning. The idea is to have consistent neck tension for bullet release and to conform to chamber as concentrically as possible. The previously mentioned 30 BR has a bullet release clearance of .001" per side.

Typically a factory chambering has a great deal of release clearance, IMO too much. If the brass gets turned then there is more expansion of the neck to seal chamber upon firing. This can over work the brass and cause premature cracking. I know all about it, I turned some 284 brass back when I started neck turning and it only lasted two firings. I realized that turning was not going to do great things in that sloppy necked sammi spec chamber.

You could segregate the "overturned" brass for practice or a comparison to your regular turned brass. See if the brass lasts or has to be retired early due to cracking.

Hope this helps

 

[newmexkid]

They are not ruined. But you may have a shorter brass life depending on your chamber dimensions. Many of us have turned brass down far more than that! I have a 30 BR that I turn down to .0105".


The issue isn't the amount of brass turned off but the dimension of the chamber neck vs the OD of a loaded round. There must be some space for bullet release. In some cases the reamer was made with a custom tight neck which required turning. The idea is to have consistent neck tension for bullet release and to conform to chamber as concentrically as possible. The previously mentioned 30 BR has a bullet release clearance of .001" per side.

Typically a factory chambering has a great deal of release clearance, IMO too much. If the brass gets turned then there is more expansion of the neck to seal chamber upon firing. This can over work the brass and cause premature cracking. I know all about it, I turned some 284 brass back when I started neck turning and it only lasted two firings. I realized that turning was not going to do great things in that sloppy necked sammi spec chamber.

You could segregate the "overturned" brass for practice or a comparison to your regular turned brass. See if the brass lasts or has to be retired early due to cracking.

Hope this helps

Thanks for the reply. That certainly eases the pain!

 

[Timber338]

I agree 100% with what AZShooter said. .013/.014 is definitely not too thin for case necks, but the dimensions of the neck in your chamber is also an important factor.

Just for the knowledge you should measure the neck diameter on a fired brass and you'll quickly know the diameter of the neck in your chamber, and then of course how much your case necks will be expanding each time your fire a bullet.

And I really like AZShooters idea of segregating the brass to see if the "overturned" brass necks crack sooner as you continue to fire/reload. That's a great experiment. and you could also compare to see if you have any noticeable accuracy difference between the two batches of brass... and please reply back with results! :D

 

[newmexkid]

I agree 100% with what AZShooter said. .013/.014 is definitely not too thin for case necks, but the dimensions of the neck in your chamber is also an important factor.

Just for the knowledge you should measure the neck diameter on a fired brass and you'll quickly know the diameter of the neck in your chamber, and then of course how much your case necks will be expanding each time your fire a bullet.

And I really like AZShooters idea of segregating the brass to see if the "overturned" brass necks crack sooner as you continue to fire/reload. That's a great experiment. and you could also compare to see if you have any noticeable accuracy difference between the two batches of brass... and please reply back with results! :D

Yes, that would be a worthwhile experiment. We'll see how this turns out after a few firings.

 

[BountyHunter]

IMO forget the neck chamber dimensions, that is not going to be a big difference.

Where you might have a more serious issue is sizing and getting neck tension on the bullet with your dies and even getting the bullets to hold.

.002 neck variance can cause issues here and that variance will cause those shots to throw to a different group at distances for sure. How much depends on the dies and amount of tension you currently are able to get.

If you have bushing dies, you can change bushings for those 10 cases.

 

[AZShooter]

I discovered something interesting when I turned down the 30 BR brass to .0105" neck wall thickness.

While I had a bushing die I decided to see what the RCBS FL die would do without the expander ball. It was a perfect .002" reduction in neck diameter. I actually quit using the bushing die! I set up the die for the exact shoulder bump and used a feeler gauge to measure the space between shell holder and die. After that I could instantly setup the FL die.

Who knows your standard FL die might work perfectly without the sizer ball if you necks are the right dimension.

 

[yobuck]

unless you have a tight neck custom chamber neck turning is unnessary anyway. lots of us prefer custom chambers of the no turn variety.
the problem you will have is once that brass is fired in your gun your standard die wont resize it down far enough to hold a bullet. unless of coarse your using a collet die. if not you will need one if you want to use that brass. might just be cheaper to throw away the brass.

 

[BountyHunter]

I discovered something interesting when I turned down the 30 BR brass to .0105" neck wall thickness.

While I had a bushing die I decided to see what the RCBS FL die would do without the expander ball. It was a perfect .002" reduction in neck diameter. I actually quit using the bushing die! I set up the die for the exact shoulder bump and used a feeler gauge to measure the space between shell holder and die. After that I could instantly setup the FL die.

Who knows your standard FL die might work perfectly without the sizer ball if you necks are the right dimension.

It is impossible for a standard FL die to "fit perfectly" for those 10 cases AND the others that are. .002 larger!

However that method you describe is a way to check out whether or not it will work for that gun and it normally solves runout issues.

 

[old_heli_logger]

They are not ruined. But you may have a shorter brass life depending on your chamber dimensions. Many of us have turned brass down far more than that! I have a 30 BR that I turn down to .0105".


The issue isn't the amount of brass turned off but the dimension of the chamber neck vs the OD of a loaded round. There must be some space for bullet release. In some cases the reamer was made with a custom tight neck which required turning. The idea is to have consistent neck tension for bullet release and to conform to chamber as concentrically as possible. The previously mentioned 30 BR has a bullet release clearance of .001" per side.

Typically a factory chambering has a great deal of release clearance, IMO too much. If the brass gets turned then there is more expansion of the neck to seal chamber upon firing. This can over work the brass and cause premature cracking. I know all about it, I turned some 284 brass back when I started neck turning and it only lasted two firings. I realized that turning was not going to do great things in that sloppy necked sammi spec chamber.

You could segregate the "overturned" brass for practice or a comparison to your regular turned brass. See if the brass lasts or has to be retired early due to cracking.

Hope this helps

I agree with this. Also, keep the neck and shoulder of brass annealed and your necks won't crack as soon.
Good luck!

 

[newmexkid]

Thanks guys.