That would be a good test. If I get time I will try it, but there is absolutely no doubt, in my mind, that the Kleenbores are much dirtier than the small rifle primers. There just wasn't any fouling in the primer pocket area with them and there was a considerable amount with the Kleenbores. There are draw backs with them, you have to prime and deprime them ( I bought 20 of them ) and you have to keep from loosing them ( I lost one ), but it sure is nice being able to just take the fired ones out by hand ( no primer removal tool ) and to pretty much do away with the 777 crud ring. I may still hunt with Winchester 209s just to be sure of ignition under bad conditions, I'll have to try them some more to decide for sure but they seem to be plenty hot enough.