[J. A. EARLY]

Jim,

First try dry firing both barrels on spent hulls. Remove the forend and see if the barrels come off. Some guns no matter how clean have to be disassembled this way. Let us know.

If that does not work you can remove the screw that holds the cocking hook by having someone open the gun as far as it will go, using a correctly sized bit. Be careful not to lose the small spring that is under the cocking hook.

Then you may have to use Brian's method if neither of the two above work.