Roundball - I guess N. Fla. in winter would be similiar to NC in that we have clear dry days and rainy wet ones :hmm: You're using 4f at range and in the woods?
4F is all I use for priming, period...as I mentioned, it's never been a problem, I just refresh it often in humid weather.
As you know, when you open the frizzen and tilt a flintlock back and forth, if the prime is dry, it'll slide back and forth in a clean pan very easily. However, if I tilt the rifle further and further, and the prime still holds together in place like it's getting a 'skin' or some 'body' to it, before it finally moves in the pan, it's way past due needing to be changed.
While sitting on stand there's not much else to do anyway so it's good therapy for me to check the prime every 10-15 minutes (flip, tilt, close)...as soon as I see that it's not sloshing around easily, I flip it out, reprime, close the frizzen. Every time I've shot a deer, ignition has been perfect...from bluebird weather to fog & mist so heavy I couldn't see 40yds.
I can understand those who pursue as much PC technique as possible like to prime from the same horn, etc...but since I already hunt with TC Hawkens, using a pocket pan primer is not an issue for me...most convenient muzzleloading accessory I have...3 grns every time.