I have a Savage FP10 (Choate Stock) that has been rechambered to 22/6mm Imp but without the shoulder being moved forward. Just the 40 degree ackley shoulder.
Quite frankly it has been a PITA. Being a std Savage barrel the barrel finish may not be what it should be. It is a 1:9 twist & my gunsmith got around 2000 rounds with his before changing the barrel. It too was a standard Savage 1:9 twist chrome moly barrel.
I too use Re22/WXR. Using WW cases & WLR primers I was fireforming with up to 47gr of WXR, it was shooting great with 47.5gr WXR and the 80gr A-Max moly. Now I am popping primers at 45.5gr of WXR. I mean what gives. My fireforming loads at 45.0gr are also popping primers.
Waiting to take it back to my gunsmith to bore scope it. There may be some damage in the barrel. The bullets are still making it to target, vel is around 3450fps but it pops the primers. BTW the 47.5gr load used to do 3520 fps and not pop the primers.
Hornady's manual has 22/6mm loads and I have corresponded with Dave Emary who has campaigned a 22/6mm Rem (Unimproved) for years so I don't think the barrel life issue is as big a deal as its made out in spite of the trouble I am having with mine. I'd love to say I have worn out a barrel through shooting it but that has not happened yet! I think I have too many guns!
If Kirby or others have suggestions for me I'm listening.
Here is a copy of my latest group:
The primer popped on the 5th shot of the group & the first shot of the fireforming load.