There is a barrel nut wrench that is specificly for the smooth barrel nuts. Wheeler makes one.
Leave it to Savage... first they invent the ugly nut that requires a special wrench... then they make the ugly nut in two sizes that require another wrench, then they make the ugly nut smooth requiring another wrench.... just waiting for the ugly nut to be made in two sizes now.... it's just plain nuts! I guess one could just a pipe wrench for all of them... ugly is ugly - right?
P.S.
I just had one come in to change barrels... and it had a smooth nut on the barrel to be removed... and the smooth wrench to remove it...
As expected the smooth wrench did nothing but slip, the nut did not move. I used a barrel vice and an action wrench and luckily the nut stayed on the barrel and I didn't need to use a pipe wrench or Vice Grips when the action unscrewed... sometimes the nut will 'lock' to the barrel and then you need to use 3 things... a barrel vice, an action wrench and a nut wrench... what a marvelous system.
I should've clarified, the nut on my 112 is actually slotted but I was just wondering
why the use of a nut for assembly, especially if it is actually a separate component from the barrel itself.