I bought one of the Montana 1999 actions last year and had Douglas put a .416 Remington Mag barrel on it. The bolt cycles like it's teflon coated, feeds and ejects just fine. It's temporarily in a Winchester M70 take off Tupperware stock until I can decide which stock to buy. Just now its between a MacMillan or Accurate Innovations.

Good luck with your projects, I think you've got some good actions to work with.