Cabela's has the Federal stuff. They say that the plastic cup stuff doesn't open up in smooth bores. I tried it in my LH Lakefield Mk1 smooth bore and it worked fine. I did some patterning out to 25' with the Federal stuff and it is awesome!!! It will break the little 'dove' clay pigeons that are about 2" diameter. So glad I scored a smooth bore .22, tons of fun on my property for mice patrol.