Just pullled the barrel on an FN mauser and found something not seen before. Maybe common, but in over thirty plus years and well over a hundred Mauser re-barrels, this is a first.

Square threads! just like a Springfield. 1.045" OD, 10 threads per inch. Barrel was stamped "Winslow Arms" snd 300 win mag.

Anyone have any insight into this?

Jim

Jim, back in the '60s one of the El Cheapo houses like Golden State Arms or similar commissioned FN to make these actions to accept the issue 1903 barrels with very slight mods. I've seen these several times and IMO they're just as good or maybe better than the vee-thread models depending upon how comfortable the smith feels with square threads. Use the same 10-tpi tool you use for the Krags, 1903s and 1917s.

Bet you had to look more than once to make sure, right? I know that I did, the first time I saw it!
Regards, Joe