Or you could form .308 to .300 Savage. likely the best solution. Trimming the neck down is a pain, but it's much more practical.
And Wiki-ing the 22-250, it is way way way too short to even make .300 savage. Why are you doing this?
22-24-25-26-27-28-30. You'll most likely need unhardened brass ("new") to have much success with it,, and yes, you have to ream and turn your necks when you are done. Way, way easier to just buy 300 Savage brass. - dan
There are a couple of boxes of Lapua 22-250 brass that I was looking at and thought it would be "neat".The .22-250 is actually 1.912" vs 1.871" for the .300 Savage...but:



























