Sorry if this is the wrong place to post this, but I can't find anywhere else in the threads to address my question. I have a standard old 870 wingmaster - modified choke, no ventilated rib, nothing. Just the gun. I would like to extend the magazine from the standard, to something that would hold a few more rounds. Does anyone know if this is possible with this weapon, and if so can you direct me as to where I could find such a piece of equipment. Also, would I need to change barrels, modify, or otherwise add something to make this happen. Thanks for any help you can give me.