Well I own one and the paper work that came with it say 1-9 and it shoots 69gr bullets way to good to be 1-12, I also own a 1-12 rifle it won't shoot anything heavier than 55 gr bullets and prefers 45 to 50 grainers.
Ok I gotta give a little here, I have the 527 varmint kevlar stocked version, it is 1-9, apparently the laminate version is 1-12.