Check this out, but I think there is one error. He listed the Winchester No. 209 A, but I think what he meant to say was Winchester No. W209 which is their standard primer. The 209A is a Federal primer which he lists further down, they are HOT! There were a couple of surprizes in there for me.
He did dispell the myth of the Winchester Primers for me though, it has been said that the Winchester W209 and the Winchester W209ML were the very same primer, that doesn't look to be the case and actually the W209ML is less energetic than the touted NEW Triple Seven primer. Looks like Winchester has three 209 primers suitable for the muzzle loaders; No. W209 (standard), No. W209ML (tan box), and the No. SML209T7 (NEW Triple Seven).
Also some good information on the Knight breech plugs, such as the power stem plug being used in the .50 caliber rifles.
In a .50 caliber bore, the tip of the 1 1/2" long stem sits at about the 70 grain level of a 100- or 110-grain charge of FFFg Triple Seven.
Also might cure some crud ring problems for some.
http://www.hpmuzzleloading.com/Technical3.html