I've never used anything like that. I've always relied on lead hammers as they haven't marred my knock offs in any way. I've also tried using those plastic dead blow hammers. They also don't mar the knock offs, but you need a pretty big one to equal force of a much smaller lead hammer. Besides, I always get the feeling using that plastic hammer that the face of it will split open and all of the shot will fly out leaving me stranded, or being forced to use a steel hammer.:hammer: