BH209 is far less sensitive to humidity than black powder, Pyrodex or 777. Hodgdon markets P-dex, 777 and BH 209. They recommend that you discard any left over P-dex and 777 before the next hunting season and use only fresh powder since they absorb so much moisture. They state that BH 209 will last indefinitely in a tightly closed container. Hodgdon also recommends discharging or otherwise unloading P-dex and 777 on a daily basis and does not make that recommendation for BH 209.
BH 209 also is intended to use full power 209 shot shell primers, not the reduced power 777 ones. CCI 209M primers are the hottest and most consistent followed by Federal 209A primers.
The 777 and other "muzzleloading" primers were all developed to reduce the blowback from Pyrodex and 777. P-dex and 777 are easier to ignite than BH 209 but switching to full power primers and cleaning the breech plug (necessary with any powder) are small prices to pay for the convenience and extra velocity of BH 209. Besides, 777 and other muzzleloading primers cost 2-3 times what standard one do.
Randy, now that you've joined the 209 family and discovered what the hype is about you might want to try either crushed rib sabots or take a look at Magnum Muzzleloading Products website at:
http://www.mmpsabots.com/There are no hard loading bullets, only hard loading sabots. There are no industry standards for muzzleloading rifle or slug gun dimensions like there are for metallic cartridge firearms so it is up to each of us to find out what works best in our rifles.
MMP makes a wide range of sabots for different bore sizes. you can save a lot of dough by buying bullets in boxes of 50-100 and buying the sabot you and your rifle like the most separately. FWIW, MMP make most of the sabots in the marketplace regardless of who's name is on the package.
The crushed rib sabots are designed to accommodate a wide range of bore sizes and bullets and have quickly gain a loyal following. They can be found at:
http://www.harvesterbullets.com/Good luck and keep us posted....
Lance