Mossburg 500a Stuck choke

[NorthStarNWT]

Hey just bought an old Mossy 500a and the choke tube has a nasty crack. I would like to remove it for inspection and replacement but it is good and stuck. I am assuming it has been in there forever. Any advice on how to get it out? gun did not come with choke wrench, I have tried the quarter trick but its not budging. Would penetrating oil leave any nasty residue that would hamper the firearms operation?
Thanks

 

[haha49]

I would just put some gun oil in there let it soak for a few hours then try again chances are it's rusted in there good.

 

[Winchested]

Do a search in the gunsmith section this question has been asked a million times.

 

[Grouse Man]

A GOOD penetrating oil, like Kroil, PB Blaster, etc. WD-40 not good enough. Give it a few good taps with a hammer to vibrate the oil in. Let it soak a day. Then heat the muzzle area with a blow dryer or a heat gun. Should come out, but if not, just repeat process until it does. USE THE PROPER CHOKE WRENCH!