One sad thing to think about is that lead shot will not be around much longer.
After buying a couple boxes of Bismuth for ducks and public land pheasants to use in my M37 it gets expensive.
The vintage M37's can not take steel.
The vintage 37's can use steel with modified or less chokes....
Lead is banned for the marshes, but in the uplands it will be here at least until there is an equivalent priced alternative....