Howdy Again boys, my this thread has certainly grown since the last time I checked it.
J.D. Yellowhammer, your problem is obvious, I'm surprised nobody else noticed. Your brass is WAY TOO SHINY.
My 44-40 or 45 Colt brass never gets that shiny, after being fired with Black Powder. Here's what I suggest you do. Next time you go to a match, dump your spent brass into a jug of water with a little bit of dishsoap in it as usual. You don't have to do it immidiately on emptying the brass from the guns, the end of the match is soon enough. Then drive home with the brass sloshing around in the jug on the floor of the car, to keep the soot in suspension. Now here is the secret. Place your jug of brass in your loading room, and completely forget about it for a month or so. After a month, your brass will be so black in the jug you will think it is a lost cause. But never fear, rinse and dry your black brass, fill the tumbler up with lizzard litter, dump in that dirty brass and fire up the tumbler. Let it run 6 or 8 hours. Your brass will never get so new and embarrasingly shiny again, it will be a dull, mottled 'dirty brass' color.
Here's a photo of some old and new ammo. The 44-40 on the far right is one of mine. That's one of the shinier ones, you ought to see the ugly ones. Ignore that 44 Special third from the right, it is a Smokeless round and does not count.
By the way, here is what Kuhnhausen has to say about head space in a SAA. First off, SAAMI rim thickness for the 44-40 is .055 to .065. Most of the Winchester 44-40 I have runs right around .055. I have a few Starline in my miscellaneous 44-40 drawer and it is running around .055 to .057. Still on the low end of the tolerance. Anyway, Kuhnahausen says that optimum headspace for a SAA in ANY CALIBER is .006. So obviously the thickness of the brass will have an influence. Also, note that headspace is ideally measured in a gun with zero endshake. Any endshake (front to back play of the cylinder) complicates matters. One can measure headspacing with the cylinder shoved all the way back, but optimum measurement will be with endshake reduced to zero.
P.S. They most certainly did have calipers and micrometers in the 19th Century. How the heck do you think they measured the parts? The firearms manufacturing industry was probably one of the premier 19th Century High Tech industries that drove mechanical inovations, like precision measuring tools. Measuring devices using a screw like a micrometer go back to the 17th Century. In 1848 a Frenchman named Palmer made a handheld precision measuring device using a screw. In 1867 Brown and Sharp began mass producing micrometers that were inexpensive enough that any machine shop would have one. Brown and Sharp also made the first mass produced affordable vernier calipers in 1851. Dial and digital calipers came a bit later.