Barrel suitability and choice

[powdergun]

So I am trying to choose a barrel for my build. It is for a R.E.M. 700 LA. Mag bolt face. Looking at Kreisler, Bartlein sites etc. I see some have 1.2. and. 1.25 diameters. Will both sizes work on this action ?


Thanks

BTW. are there some contours that will not work for a 300 WM . Right now I am looking at heavy Varmint contours