I have an old MK85 from the early 90s and have always used 100 gr of Pyrodex Select and some RWS-1075 primers that I think are German made. It shoots great and I have never had a misfire. I haven't been able to find the same ones. What are people using now. I am happy with how it works and don't want to change out the nipple or anything.
In the past I used CCIM primers with Pyrodex, because that's what I had. There is no need for a real hot primer with Pyrodex, since it can be ignited with a #11 cap. I'd go to the local supply & see what they may have in stock, try them.