Just got a Lyman deerstalker in .50 percussion and am starting to get my supplies I need together to go with it

Concerning carrying powder which do you prefer a traditional horn? Or a brass flask?

Do the flasks have any lock other than the spring valve?

Looks like it would be easy to spill powder carrying it around in the woods in your possibles bag

I never had any problems carrying powder either way. You can buy rapid reload tubes for faster follow-up shots if you're not going 100% old timey accuracy. The spring loaded brass flasks are pretty strong and its not likely they will spill. See Mid South Shooters Supply for their excellent selection of black powder supplies, tools etc. Make sure ALL the tools you use while handling, working with powder in any way, ARE MADE OF BRASS. No sparky.

Get the Lyman Black Powder Handbook:

https://www.amazon.com/Lyman-Powder-Handbook-Loading-Manual/dp/B0000C6I4U

Thank me later.

ETA: I always had the best performance using roundballs or conicals, depending on the twist of the barrel. I never had any real luck getting Sabots and jacketed bullets to shoot well for me in my Lymans. Killed multiple deer, hogs, and a turkey with my Great Plains 1 in 60 twist barrel. Did the same with my Great Plains Hunter rifle, which has the 1 in 32 twist that can be used for RB, conicals, minie balls, and Maxi-balls.

I have it, I bought it off Lyman's eBay site for like $5 with a little tear in the cover

All righty then, off to a great start

I will answer any questions you may have, or point you to someone who can if needed.

I tend to prefer the flask over the horn, but then again, for me it depends on if I'm doing any reenacting at the time or not. For Civil War I use the flask, for Revolutionary war I use the horn.

Flask is somewhat easier than the horn in that you can use a pre-measured tip on the flask to load a single charge, whereas with the horn you have to use a separate powder measure.

Just my thoughts anyhow.

I prefer a horn over a flask, I dont use a priming flask and I find it easier to control the amount of priming powder in the pan of my flintlock with a horn than it is with a flask.

Both would be appropriate.  It depends on what you want to do.  I prefer horns myself.

I've got a horn but that's the same reason I use a flask- you can get measuring tips for horns though.  It's easy to do one handed just by putting your thumb over the opening and tipping it over and filling the measure.  Honestly, most of the time I don't even carry that hunting anymore, usually just one speedloader with a powder change and patched ball and an in-line capper in my pocket.  If I ever get around to putting my shotgun kit together I might try using a horn again.

Late to the party, but: For reenacting, I use what is appropriate for the time period.  For hunting/range, I use pre-filled rapid reload tubes.