emr; Yes, I have tried APP in my flinters. I used APP, FFFG, as a main charge. I used Goex FFFG, and FFFFG, as prime charge in the pan. (no difference in ignition). It is not reliable enough. Delay, and hangfire. It works good in my percussion sidelocks, but not reccomended for flinters. I find Goex FFFG, as the main, and pan charge to work the best. Instant ignition every time.