Marlin lose barrel

[Nevada Mark]

Sad news  – Loaned my Marlin Cowboy to a friend and he managed to drop it and crack the front stock. Good news  - I have replaced the stock but Bad news  - the barrel is very lose, it will move back and forth and up and down about ½ inch. Anyone out there can tell me how to tighten the barrel up and keep it from moving around so much?
Thanks[/size]

[Pettifogger]

It's hard to visualize a barrel moving 1/2" up and down in the receiver.  If it moves that much you have severe damage to the barrel threads and/or receiver.  I would send it back to Marlin.  It sounds like it is so out of spec that it might be hazardous to shoot.  That isn't something you are going to fix yourself.