Neck turning re-visited.

[NF1E]

Well, some friends have convinced me to turn necks on a batch of new Lapua .308 Palma brass. Working on 100 this morning. Finished 50 taking the neck thickness down from .016-.017 to .015. Feels normal to get this gear back out and in service again. Will see if there is as big a difference as my friends tell me there will be. Used to be common practice, for me, with surplus brass but haven't turned necks since going to Lapua. Whatta Hobby!

 

[jackieschmidt]

What is the neck size of your chamber? You just added .002 to .00025 to the overall clearance for your loaded round, which, depending on your chamber’s dimension, could mean yo have as much as .007 neck clearance.

That seems a little excessive.

 

[NF1E]

Much more concerned with neck tension , at this point, than clearance. This is new Lapua brass and after the first firing it should be equal to the chamber dimension and future preparation will be determined at that time. Just trying to start off on an even keel. I do realize sizing from this point will have less material to work with. Much of my other brass starts out less than the .015 which is being dealt with here. Whatta Hobby!

 

[Straightshooter1]

Well, some friends have convinced me to turn necks on a batch of new Lapua .308 Palma brass. Working on 100 this morning. Finished 50 taking the neck thickness down from .016-.017 to .015. Feels normal to get this gear back out and in service again. Will see if there is as big a difference as my friends tell me there will be. Used to be common practice, for me, with surplus brass but haven't turned necks since going to Lapua. Whatta Hobby!

View attachment 1728552View attachment 1728553

Fascinating . . . that your virgin .308 Palma brass measured .016-.017". That sure seem awfully thick for Lapua brass??? Mine measured, like my other Lapua brass, at .015 or somewhere just under .016. And I turn them all to .014".

Indeed. . . whatta hobby!

 

[Straightshooter1]

What is the neck size of your chamber? You just added .002 to .00025 to the overall clearance for your loaded round, which, depending on your chamber’s dimension, could mean yo have as much as .007 neck clearance.

That seems a little excessive.

I'm sure there's some point where excessive clearance will be a problem. I'm not sure where that is. For shites and giggles some time ago I had turned some Federal .308 brass down to .0125" to see it there might be some improvement in performance or a disaster after reading about what some competitors were doing and saying they turn "thin to win" in no turn chambers. And actually, those brass did pretty well for me with no issues I could see. But I stayed with just turning my brass to .014, which I'm comfortable with and has worked out just fine for me.

I'm not sure as to what exactly my clearance is for my Krieger barrels. I know the OD my fired rounds are at .343" and my loaded rounds are .336". I'd guess my chamber would then would be something like .345" for an overall clearance of ~ .009???

I'm wondering, what issues there are with excessive clearance?

 

[NF1E]

Learning discussions , like this, can be a help to so many loaders trying to get things right. differences of opinion are valued assets to conversations. Suggestions welcomed, criticism not so much. Whatta Hobby!

 

[NF1E]

Doing a little experiment with some LC 01 brass turned to .014 neck thickness, HBN coated 110 gn Sierra varminters over 46 gn of Varget. Dang I love playing. Whatta Hobby!

 

[Murray Brook]

@NF1E
I see you use the Hornady neck turning tool How do you like it.

 

[NF1E]

@NF1E
I see you use the Hornady neck turning tool How do you like it.

Works well for me, then I don't know any better. Whatta Hobby!

 

[Steve Donlon]

I'm turning mine down by .012" and now have .005" clearance instead of .003" with better results according to my targets.

 

[NF1E]

Results tell it all. Thanks for all the input guys. Whatta Hobby!

 

[jackieschmidt]

The “turn thin to win” has its origin in the Short Range Benchrest crowd.
When I first started shooting Benchrest way back when, many of us strived to keep the loaded round clearance at no more than .001 inch overall, thinking that super precision fits were where accuracy laid.

At some time, it dawned on someone that these super tight tolerances were actually cause flyers. The cure was to give the loaded round a little ,ore overall clearance to insure good positive bullet release from shot to shot.

So, the term “turn thin to win” came about. In truth, it should be, “turn a little thinner to be a winner”.
The reason being we are only talking about .001 thinner at the most from what many were doing.

So instead of having the loaded round with just .0005 clearance, we have around.0025 loaded round neck clearance. I know several shooters who even go to .003 overall clearance.

In my 6PPC rounds, my reamer cuts a .269 neck. I try to have a loaded round neck dimension at around .2665. The fired necks have that nice sine wave soot making, and one of my bullets will slip into a fired case with no interference.