Dry reddish color film residue from BP ??

[roundball]

With cold weather here again and looking ahead to starting back shooting on Satutrday mornings after hunting season ends, I remembered something about powder residue that I noticed last January & February.

Shooting my flintlocks in cold weather months with very low humidity, I noticed a couple things:
1) You hardly ever have to bother wiping the pan when the humidity is real low, and that's a good thing of course;
2) I noticed a very faint, light coating of a dry reddish film beginning to appear around the vent liner and on the pan...and occasionally see a flake / speck on a patch, etc.

I only seemed to notice it during those cold low humidity months...and with different rifles and calibers.
I only use Goex FFFg main and Goex FFFFg prime so I don't know if it's unique to Goex or not.

I haven't noticed it during the other more normal high humidity months of the year...but then, during those months I'm wiping/cleaning the vent & pan after every shot anyway to eliminate the soup effects of humidity, so it probably wouldn't have had a chance to show up anyway, dunno.

Anybody seen this faint reddish, dry, powdery film...know what it is, what causes it?

 

[Zonie]

For those wondering what the answer to this question is go to
http://www.muzzleloadingforum.com/ubb/ultimatebb.php?ubb=get_topic;f=11;t=000085

and read Voyageurs comments on this phenomenon