I had a 7GNR Contender Rifle that was stolen. My hunting friend has a 7/30 Waters rifle. I gave him my remaining factory 7/30 Waters ammo. But I have a few boxes of once fired 7GNR cases.

If I anneal the neck and shoulder of the 7GNR cases, can they be resized back to 7/30 Waters cases? If so, do I have to use a 7/30 Waters FL die or could I use another 7MM die with similar shoulder and case diameter?

I have a Contender in 7GNR as well and could use the brass. Most of my 7-30 Waters brass is formed from 30-30, but I might have some 7-30 brass stashed away somewhere.