Reforming .308 winchester brass to .260 question.

[Warbone]

Bought 100 .308 winchester brass to reform to .260 remington, for a new rifle i am getting.
.308 brass case lenght is about 2.008.
When i resize it with my .260 die i get about 2.015 to 2.020.
Hornady case trim length shows 2.025, and max length of 2.035
Is this going to cause any problems?

I planned on fire forming these resized brass to break in barrel and then either neck sizing or FL sizing.

 

[tnrednk74]

I believe that's pretty common if you don't neck down 308 to 7mm/08 and neck turn before going to 260! That's why I just buy Lapua brass! I would not shoot a 2.015 case in my 260!

 

[FLIGHT762]

A couple of threads that might help you.

http://www.snipershide.com/shooting/snipers-hide-reloading/132638-forming-260rem-308win.html

http://www.snipershide.com/shooting/snipers-hide-reloading/190797-neck-down-308-win-260-rem.html

I don't reform 308 to 260. I neck up 243 to 260, although you will have to deal with donuts doing this. I do have a Forster inside neck reamer to deal with it. Most here will agree it's best to get 7-08 brass and neck down to 260.

Both 308 and 243 brass will be short as they are both 2.015" SAAMI max. .260 & 7-08 brass is 2.035" SAAMI max.

If you do decide to neck down 308 brass, you may have too thick necks. The only way to tell will be necking down and loading a dummy round and see if it will chamber easily. If you're shooting a factory rifle, you might be okay.

 

[Warbone]

Ill Check out the 2 links you put up flight.
As it is right now the only brass i could find anywhere was winchester 308 brass, so this is what i have to work with.

 

[Aimsmall55]

I formed some creedmor brass out of federal .308 All I did was anneal the heck out of it. Then neck sized it then annealed again on the shoulder area and fl sized. Then I bumped the shoulder as needed and reamed the neck. Did it just to see but it came out fine. Just needed to be fire formed. As stated this was "I wonder if I can do it" type deal. MUCH to cumbersome to do where as you can drive 1 hour and find some regular brass.

 

[Warbone]

From what i have read case lenght of 2.015 or better should not be a issue. Issues come with neck thinkness.
After reforming brass i get a lenght from 2.018 to 2.020. Neck thickness is .290. After seating bullet i get .293 to .294.
which gives me .004 to .003.
Thanks for the info all.
I wont really be able to tell if this will work until i get my new rifle.