Over the range of bullet weights common for target and varmint shooting, the theoretical relationship of twist and bullet length doesn't always hold. You are just going to have to do the shooting, tough as that may be. A 60 grain flatbase may shoot well in your 1x12 Remington, I know the Berger does in my old 788 with that twist. On the other hand, the Berger 52 grain bullet is more accurate in my 1x9 ARS Ruger than the 60. And the Sierra 52 gr BTHP Match is accurate in everything I have tried it in, from a 1x7 HBAR to a 1x14 .22-250. I seldom buy anything else these days, although I have some Remington 50 grain Pow-r-lokt that do very well. But I am not a highpower competitor who needs 69 grain bullets for midrange and 77-80 for long, nor a 3-gun shooter with M855/SS109 ball, either. Those need more twist.