WinT7 primers worked fine for me with loose T7 powder. Never had a single ignition issue. I cant say for sure if i ever used them with T7 pellets but they worked fine with Pyrodex pellets.

No primer seemed to help the crud ring much with the pellets but the WinT7 primer had some effect on loose T7. They made a bigger difference in my old ThunderHawk...not 100% sure why.