Tim,
That one tent we were in that had the "air gun pellet" mould also had a scale model Coehorn for shooting Golf balls...cute as all get out and $395. It looked exactly like the ones out in the firing line to a "T"
I also made contact with the fellow standing on the top of this "A" frame. I hope to be able to carry on a conversation with him shortly via Email.
That "A" frame for the rest of you is what they use to mount and dismount that 8 inch gun.
Next spring I am going to make it a point to go out for the setup. There was a lot of things going on to make those guns shoot. Lots of aiming stakes, plumb bobs, levels and such.
Here's how you swab the bore out on an 8 inch.
You reach in with a great big towel and start wiping. They were also using the same technique on the coehorn.
Powder going in the mortars was loaded loose. It was all pre measured and put up in plastic medicine bottles for the 8 inch and plastic film cannisters for the Coehorn. The loader just reached in and dumped the powder in the chamber. There is no way that the amount powder they were putting in could have filled the chambers. The Loaders were all wearing leather gloves and welders sleeves that covered clear up to their shoulders. They all turned their faces away from the muzzle while loading.