It has been quite a while but I think Remington 700 used to be purchased by hobby smiths building custom Mauser rifles. They would turn down and rethread the receiver to fit the Mauser receiver. Mauser receivers come in large ring and small ring. Large ring have a shank diameter of 1.10", small ring are .980" shank diameter. Both are 12 TPI, 55 degree Whitworth.
Remington take off barrels use to sell for $25.
I have used worn out Mauser barrels, painted fluorescent orange, as survey stakes and , unpainted, as an axle for hanging wire spools on when running electrical wire. You can hang three or four 500' wire spools at a time on a Mauser barrel.
Vlad