I read in another forum this guy said he was using a primor for a 410 shotgun shell instead of the 209 primors with 777 pellets and he has no crud ring. He said the 209 primors had too much force and was unseating the pellets slightly before they can burn. Anyone else ever heard this before? I know you can change your Encores over to use 25 cal. casings instead of 209 primors for sorta the same reason, but I didn't know a 410 primor was any differant than a 209 primor.