i need opinios on a rifle build, open to all info....

i have a 300 win mag 700bdl, have had it 20 years, grew up on it to be honest, she ain't grouping like she used to, looking to build a tactical style 300 win, want to go with a 22" heavy/varmit style barrel. (shilen, lilja, or hart) and maybe a full pillard hogue or hs stock, plan on using the factory trigger, i want the action tued, and any other accuracy tweek that can be done, i am not a reloader, so will be limited to factory ammo, is 22"s to short?, gun will still be used for some whitetail hunting out of shooting houses, probably going to stay with 3.5 x 10x50 leupold, or may possible try a triicon 2.5x10x56mm accupoint scope, vast majority of ammo will be 180 gr loads, open to any opinions or suggestions, thanks