Tikka T3X chambers a 22-250 in the varmint with 1:8 twist which would run heavy 80gr bullets about 300 FPS faster than the 223 and should easily get out to 1000 yards, more powder and faster bullets will of course be harder on the barrel but that's one of the trade offs if you want faster and flatter
I looked for that rifle in their line-up when this thread first started and couldn't find it. I wonder if they've dropped it?