I have a 1:10 6mm AI Encore, very similar to yours. It shoots 70 gr. BTs, 85 gr. NPTs, and 90 gr. ABs very well and all of them group in to 1 -1 1/2" at 100.
I use the 70s for varmints. Did a rockchuck at 412 in ID this year. I've done deer at 400 with the NPT.
Just killed a doe yesterday with the 85 NPT at 226 yds. High shoulder dropped her.