I was given one of those leather hunting bags, with the shotsnake attached to the strap. The bag is HUGE, but I decided to carry it anyway. Nothing says you have to carry everything you own in it! The irish measure works okay, but as I have said here before, I found that the measurements marked on the dipper that comes with the device does not accurately throw the indicated amount of shot, using #5 shot. So, I take the dipper full of shot out of the snake, and pour it in a separate measure that I have set for the amount of shot I want to shoot, with that separate measure based on a weighed volume of shot. It takes me 1 1/2 measures of shot from my snake to get the shot charge I shoot, but that is okay. I am not in that much of a hurry. The Irish snake works fairly well, particularly if you don't try to fill it to the maximum capacity. I believe it can hold almost 2 lbs. of shot, which is a lot of weight to be hauling around on your shoulder.
As for ramrods, My double barreled 12 gauge has the ramrod thimbles removed. I carry the rod under the bag strap down the middle of my back, with the jag tucked into my belt. The rod sticks straight up behind my hand, interferes with nothing, and I can grab the rod and get it into action with the swipe of a hand behind my neck. I get some curious looks from modern shooters, which I ignore, and of course they all gather around to watch me load my gun after I kill that first bird. By the end of the hunt, they think I have come up with a good solution for carrying a loading rod, and they are impressed with the killing ability of a blackpowder shotgun.