Have you considered a custom barrel for the 300WM where you specify the barrel length, twist rate etc. A match grade barrel in 1:8 twist for that caliber should not be that difficult to find.
Welcome. wish you the success in our rebuild. If you have not already purchased the parts mentioned; may be less painful to buy a rifle already configured and ready to shoot.
Brother I concur we must be prepared for when we leave here. Our bodys are only temporary shelter.
But if my math is correct Almighty God had 600K plus males train and prepare for battle. I do not fear because I Know Almighty Holy Living God. Even the disciples were told to take a sword.