Excuse me for stickin my nose in here, but I just couldn't resist givin you my recipe. No, I'm not shootin a Tikka; I'm shootin a Remington Varmint Synthetic with a 26" barrel. It has a 1 in 12 twist. I'm using Norma brass; Federal 210 match primers; 44grs of Hodgdon's Varget powder under a Hornady 165gr Spire-Point boattail, or an Interbond-same weight. I'm gettin 1 inch groups @ 200yds. That's right.....200yds. I can't tell you about oal, as your rifle is different than mine, but maybe you can incorporate some of this info, and hopefully get good results. Good Luck! jd45.