Necking up from .260 to .308

[Firearriw]

Morning. Long story short. Have a good amount of .260 Lapua brass from my last barrel that I was thinking about necking up so I could use it for a friends .308. Never necked anything up before and I have expander mandrels to go to .270 and then .308.

Are there any issues with necking up a case?

 

[Hecouldgoalltheway]

I made a ton of .260 brass from .243 brass. Just ran a full length, did it once and it was done. Thats a little bigger stretch though.

 

[memilanuk]

Might have some issues where the thicker shoulder material is now part of the base of the neck... leading to donuts. Depending on what bullet you're using, and if it sits down that far in the neck, it may or may not be a problem.

Ironically, long ago and far away, before Remington domesticated the .260 Rem, some NRA HP Rifle shooters used to make "6.5-08" brass from either Winchester .308 (neck down, and maybe have to neck turn) or Lapua .243 (neck up, and maybe fight with donuts). I went the Winchester .308 / neck down route, because neck turning was less of a PITA than reaming out donuts, at least back then.

 

[Firearriw]

Damn. Didn’t think about the donuts

 

[memilanuk]

If you do have a bunch of it, I'd say give it a try - maybe a box of 50 - before you commit one way or the other. Fire the cases a few (3-5) times, and see if its actually a problem in your situation, or not.