There's been a lot of nice priming horns shown. What's not been asked is, is there a need? I've got a nice small flat horn that I use, but that has now evolved into a hunting use primarily. I shoot 3fg in all my guns. I can't tell any difference between 3fg & 4fg ignition times, so I prime with my powder horn to keep things simple. My priming horn gets used when hunting where I can carry it along with 2 or 3 premeasured powder loads and a loading block with balls and lubed patches. All this fits in my hunting coat's pockets, keeping things really simple with no possibles bag needed.
Dave
When I hunt I do not use a horn at all. That is unless I'm doing a HC hunt back East where I'm mostly just sitting on my butt. We dress the part so we carry horns and such. But since we are hunting in postage stamp size properties, the only time a horn and bag is going to get hung up in brush, is when retrieving game.
Here in AZ I just have a a cartridge box on my belt that holds five paper cartridges. It has a short starter attached to it. I use a five shot ball block that hangs from my neck. I use the orange plastic bottle shown in my previous post to prime with. It stays in my pocket.
Hunting out west involves mostly spot and stalk in my area. Usually I cover an average of 6 miles a day. Don't need a bunch of stuff hanging all over me.
Day pack and binoculars are a must though.