Pretty easy to Duracoat your flutes, do your base coat(s) then tape it off and spray a very light coat of black, then take some ~#400 wet sand on a block and either spin the bolt(easier if it's a stripped Savage) or by hand as the block will only take off the black that's not in the flutes. Don't take off too much or you will get the base coat.
Fixing To Send A Couple More Remington's In..LRI Gets $25 For A Remington And $35 For The Tikias.I Dou't You'll Bet The Price Any Where. I Have Used Twisted Barrel. LRI And Karl A long With Few Others Over The Years..