Re: 220gr Match King\'s in 300 Ultra.
Hope your enjoying the new rifle as much as you DID your wife.
Anyway, I would stick with the Rl 22 from your 26" barrel. It seems to be working just fine.
If you had a 36 or 37 " barrel I would say stick with the H870 and see what happens to the velocity and the accuracy.
Your accuracy seems fine right now and so does the velocity.
If you don't have the obvious pressure signs, you can venture on up a tad, VERY SLOWLY and see what happens to the accuracy.