Well it is easier done than said. Let me rant first before I try to assist. Just because a gun is capable of disassembly doesnt mean you should! More take down guns have been ruined by constant disassembly than by actual wear. I have owned many take down guns and only disassembled them 1 or 2 times. I have seen a model 12 that had been disassembled so many times the threads were actually worn smooth. Now I will try to help. The model 12 was designed to be adjusted if ever it was shot so much as to need it. First disassemble the action from the reciever. Look at the barrel end of the front half. You will see the chamber end of the barrel is surrounded by a threaded sleeve. This is called the adjustment sleeve. The following script is taken from a Winchester bulletin. quote " The barrel is equiped with an adjusting sleeve threaded on the chamber end of the barrel in the back of the reciever extension which is also threaded on the at the chamber end. This sleeve is adjustable on and off the threaded end of the barrel to produce a tight joint condition between the riciever extension and the reciever into which the barrel screws. The adjusting sleeve is provided with a number of teeth on its outer rim. The reciever extension has a recess containing the adjusting sleeve lock, the slide moving up and down with 3 teeth on inner end which mesh with those on the rim of the adjusting sleeve when the lock is held in place by the lock screw." Next quote, " Turn adjusting sleeve one or more notches counter clockwise to tighten the draw" Whew! Im confused, I would assume you are as well. To summerize, after taking the gun down you should be able to see how to adjust the threads on the barrel end as to tighten the fit between barrel and reciever. Once down I would suggest that futher take down be very limited.
(grandma is scared to death of guns
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