Lenard & Pete,
B&P have a tremendous business relationship with Gamebore, the shot you describe sounds like Gamebore's 'Diamond' shot which is a very good high quality product, very hard, very polished, very round shot.Gamebore have various methods of shot manufacture and indeed very often combine methods of manufacture to produce high quality shot.It is my opinion that the plating of shot with copper or nickel is more of a gimmick than being practical.The thickness required to be beneficial is not practically applied.
