We were actually talking about the "Brand New" Mauser 98 made by Blaser in the Blaser plant, which has the Mauser name attached to it and is not actually made by Mauser themselves. The was never any question about the older pre-war Mauser's, and I never mentioned them, they have always been threaded. Not sure what the fuss is all about, it was purely a question based on the Blaser reputation of using the latest manufacturing techniques.

Anyway, as to the question of take-down attachment methods, Westley Richards have in the past used their own two-start square thread which is really a big Bayonet thread.
Ritterbush has a system where the receiver is bored out and a barrel with a precision ground outer breach diameter is inserted into the receiver, then clamped by a screw which is fitted cross ways through the front of the action, which has a length ways slot underneath.
Dakota use the same system but the Dakota is classed as a Model 70 Type action rather than a Mauser.

Waidmannsheil.