When the receiver is locked closed, remove the forearm using the lever on the bottom of the wood. Next keep a firm grip on barrel and receiver, break the gun open by the lever on the top of the tang. When broke open the barrels will lift off and separate from the receiver and stock.
Download a manual from Browning or take it to a gunsmith
The browning web site will provide this info.
John Moses Browning. The Browning Superposed was the first practicle over, under shotgun
Let a gunsmith do it.
Do not atttempt this. Find a gunsmith.
You will have to call Browning to find out.
Best bet is to ask a gunsmith for help.
Best left to a trained gunsmith
Leave this to a qualified gunsmith, trust me on this.
Check under the top lever.
Foillow the owners manual on the Browning website at: http://www.browning.com/customerservice/ownersmanuals/index.asp
A staple of the Browning line since the 1930s