Hi HandiMan,,I just registered here because I thought I may be able to help you a bit.
I have a bag of copper BB that weighs 5# on the bathroom scale......also a 5# bag of copper 2's. Had them since I used to reload for geese,,and then that and all lead was outlawed....so that tells ya how old it is.
But I would let you have it for whatever shipping is and a little extra for my time and travels.
I can't remember how I loaded them,,but I know I was using buffer in the shells also and they were only 3" mags. with power piston wads I think.
Pm me if you're interested.