Good luck with your rifle, RC and airguns, that's one deep money pit.
Looks like it is time for you to try H&N Field Target Trophy, or JSB Exact Kings in your Rushmore. Just remember to thank me later. All my Crosman NP and NP2 air rifles really like them. They produce sub-nickel size groups in my springers, and sub-dime sized in my PCP at 25 yards.