I started another thread here about my adventures with chronographing 45 Colt Black M-Z rounds and ended up saying I was going to give up and spend the money to acquire some real black powder.
Well I did that, buying a couple cans of Old Eynsford FFFg. My first trip to the range was "eventful". My arthritic hands don't enjoy full BP 45 Colt loads like they used to so my ammo was 31g of FFFg behind a 256g RNFP lubed with SPG. First 5 rounds went OK but before I finished the second cylinder it started dragging. By the 10th round I had to index the last round by hand as the fouling was so thick between the barrel and cylinder.
Now I should probably explain this was shooting my latest acquisition, a late production USFA 45 Colt, one of their "Pre-War Models" complete with the black powder frame. This gun is so well fitted, with a minimal barrel cylinder gap it just didn't tolerate the BPs fouling build up. I was pretty disappointed thinking I would have to relegate it to smokeless powder reloads, but...
A week later, while loading up for my next trip to the range, I noticed 20 of the Black M-Z rounds I had intended to chronograph but were now just setting on the shelf since I thought I was giving up on Black M-Z. I decided to take them along and see how the USFA like them as one of Black M-Z's claims to fame is reduced and easy to manage fouling.
After shooting about 60 rounds of smokeless loads I got to the Black M-Z rounds. The first five went off with satisfying clouds of smoke and that odd smell it has. The cylinder was turning freely so I fired another five (I only load five rounds, starting with the hammer down on an empty chamber). The cylinder still turned easily and continued to do so for 4 cylinders (20 rounds total).
Looks like I will be shooting fake black powder in my fake "Colt SAA". And having said I was giving up on Black M-Z, I have to say crow doesn't test so bad with a little salt & pepper, and a lot of salsa! (LOL)
Dave