I picked up a number of barrels from an estate, this one I do not recognize. Its a Schneider barrel 24 inch shank is 1.060 diameter .880 lenght and 18 tpi.
.308 caliber.
The shank "looks" like a Mauser flat on the end, not recessed like a Remington, but none of my books show those measurements
The previous owner was a target shooter.

Dimensions of a M700 except for the 18 tpi. Probably some kind of a target action Remington clone, that they threaded differently.