.014 neck wall thickness is about...

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Right for 338 lm Lapua cases ?

Decided to give half my 2 times fired Lapua cases the royal treatment today.

1.
necksized them with .366 bushing (that decapped them also).
2.
Bumped the shoulder with body die (they started to be difficult to close the bolt in the TRG42).
3.
Trimmed them to 2.715 (including chamfer and debur).
4.
Mic neck wall thickness with Mitutoyo Micrometer. Got varying thickness from .014 to .016 in many samples .
5.
Hand outside neck turned them all with Forster Hot 100 to a nice .014 even everywhere.
6.
Annealed the 50 cases using my brand new Bench Source annealing machine. That tool is great BTW.

My question is...

Is 0.014 right for 338 lm Lapua neck wall thickness ?
When turning them, the carbide cutter took off brass all over the neck surface.

Did I took a right amount off those neck ?
I checked concentricity with Sinclair gauge and the necks are about 0 runout (needle barely moving).

What do you think ?

Mush
 
366 bushing will leave no neck tension on the brass. consider 364 and 363 as a start.

14 thou thickness should be just fine. Glad to hear the Forster hand turner is working well.

I can offer Bench Source annealer for less then buying direct due to huge cost of international postage and brokerage.

If you need more 338LM brass, I can offer a great alternative that is far less money and pretty much works the same.

Jerry
 
I use 2 thou neck tension on my brass when loading, no movement in the bullets during recoil, works nicely for me.

As Jerry mentioned, those sizes are a good idea to start with. Neck tension is a good idea when dealing with box magazine fed rifles.
 
Mystic Precision said:
366 bushing will leave no neck tension on the brass. consider 364 and 363 as a start.

14 thou thickness should be just fine. Glad to hear the Forster hand turner is working well.

I can offer Bench Source annealer for less then buying direct due to huge cost of international postage and brokerage.

If you need more 338LM brass, I can offer a great alternative that is far less money and pretty much works the same.

Jerry
Click to expand...

With untouched necks. .366 bushing gave me 2 thousands pressure.
With them turned I will probably go with .365 or .364. I'll have to check and measure.

Mush
 
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I seated some bullets today. The bullet seated turned necks measured 0.366 outside dia instead of .367 normaly.
So I passed all the brass thru a 0.364 bushing.

I just wish that all that works will drop Es and Sd.

I'll let you know !

Mush
 
I just turned a number of 338 Lapua cases, I removed 2 to 2.5 thou, this had some 100% cleaned and some not even touched, but they are all now the same, still didn't help me though as I have larger issues then brass, I am using a 365 bushing , seems to be right where I want tension.
 
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