Necessary to fireform new brass

Lago

I reviewed the threads on fireforming brass but they were related to forming the brass from one calibre to another.

I picked up some new Remington 22-250 brass at a gun show and am using a neck-sizer die. Is fireforming necessary or just load and shoot?

Thanks

spclark

To be really thorough, you should full-length resize even new brass, in any caliber. Then trim to length, chamfer, load & shoot it (not high power loads though if you want the longest lifespan for each case), THEN do your neck-size only. This makes the cartridge conform to the particular rifle's chamber you shot it in (and it should NOT be fired in another rifle again without full-size resizing). Fire-forming is typically only resorted to when you're making something you can't find out of something that you can - within reason.

coyote-man

Lago,
On all new brass I just neck size for the first load and then I load just a standard pressure load, nothing hot. Then I check the head space with a RCBS Precision Mic and this tells me where I am at. After a couple of firing you will know what your chamber size is by checking the casing with the RCBS Mic. Then FL just a couple thousands under the chamber and your set.
I just finish shooting my 22-250 today with my new Shilen Match barrel and using the 55 V-Max (moly) w/36 gr. of H4895 the biggest group was 1/2" at 100 yrds. Did have one group that was a 1 hole for three shots.
One thing I have notice over many years that the Win. brass shoots much better than Rem. brass, I use no Rem. brass for my 22-250's any more.
Good luck and good shooting.