I pattern my shotgun but only to a certain point because I normally use only three shot sizes plus a Turkey load. All from the same company. Go Winchester When I'm trying a different type of ammo, either shot size or manfacturer, then I'll pattern about three or four rounds. Same for when I change chokes but shoot the same shells. It just gives me some idea of where my shot pattern is concentrated. I have seen dramatic changes a few times especially when switching from Winchester to Remington to Federal etc..