neck turning for 260?

[simplerider]

I have read about having to neck turn 260 cases that are sized up or down from 243, 7-08, and 308 (typically using high end brass i.e. Lapua, Nosler, Norma). I have also read that some have not had to turn necks at all, they just resize, load and fire with no problems (typically using Winchester or Remington brands from what I gather).

How do you know when you need to neck turn?

Does anyone have any experience with resizing the different brands of brass?

And yes, I have tried to get my hands on 260 brass from Lapua and Remington, but I can't wait for months on end on the backorder lists.

 

[Unknown]

I buy Winchester 7mm-08 brass, and size it down. It is cheap, easy to find, and easy to neck down. It will not hurt anything to turn necks before you load cases for the first time, but I think it is unnecessary to turn them that soon. I would shoot the brass 2-3 times, then turn, and anneal the cases. Then you should be able to shoot them another 3-5 times between annealing them again. I find that once turned, I do not need to turn cases again. Annealing every 3-5 firings keeps the necks from cracking so soon.

 

[turbo54]

1. Measure the neck OD of a few pieces FIRED (from your chamber) 260 headstamp cases.
2. Add .0015" to largest measurement found in step 1, consider this new number to be your chamber's neck diameter.
3. Neck down several 308 cases --> 6.5mm
4. Load bullets into the necked cases
5. Measure loaded necks

If your calculated chamber neck diameter is at least .003" bigger than the loaded, necked 308 cases...no neck turning required.

If not, you should turn them.

 

[427Cobra]

I turn all my 260 brass to .0135 using a 21st Century Shooting Systems turner, I mostly use Win 243 or 7-08. My opinion is all brass needs neck turning, I know that is not the wisdom shared by most here, I found since I started turning necks that my runout is about nothing, no collet die, no turning the cases when seating, or any of the other tricks used to combat runout issues, accuracy has greatly increased due to even expansion of the neck, SD/ES also became much more consistent over time, and fliers have all but went away, of course 243 necked up needs the shoulder that is now neck turned away to prevent donuts, 7-08 becomes slightly thicker from being necked down, once all the 243 and 7-08 turned there is no difference in them, I don't separate them. Rem 260 brass also benefits from NT, but because the primer pockets let go much sooner than Win brass and Rem brass cost more I don't bother buying it any more, I have never shot Lapua 260 brass due to its cost.

 

[korykhunter]

How precise are you trying to be??? The more you can do to make your brass the same dimensions the better your accuracy. If your necks get to thick you can have pressure problems. I agree with what has been said above and add a good way to check your brass is making sure you can slip a bullet into a fired case. That way you know your chamber is allowing the bullet to leave the case without excessive pressure.

 

[msiebert]

I use LC LR to my 260 brass. I run it thru a 308 die, then 7mm-08 then finally to 260. I have shot it that way without outside neck turning but found that it was better after being turned. Military brass, even the "long range" stuff usually has inconcentric necks. I just give it a little clean up cut...it doesn't need to be cut completely all the way around. I definately anneal the necks because all that sizing work hardens it.