Thanks to all. Info I needed.
This Mark III was manufactured 1933-1937. I ordered a couple of days ago 200gr .361 bullets That Matt said were for the Mark II. I had read in several posts at other forums that the best accuracy is with the 200gr .361, not 146 gr. Well I shot it this AM for the first time and that's all BS. The 146gr Remington Match did fine. Me not so much.
I think the key here is the .361, not the 200gr. The best measurement I could get off the Rem. was .357. The targets should improve with 146gr .361 bullets. I'll leave the 200gr alone. I did not come here to not listen to your advice.
Getting the cylinder off was what I really needed for proper cleaning. A bit of a PIA with the cylinder on.
I am very pleased with this Mark III. It's built like a little tank. Heavier SA & DA trigger pull than I am accustomed too. Practice will fix that.
I am attaching target pics. 7, 10, 20, & 25 yards respectively.
At 7 yds my first six shots. All are single action although I did pop off 6 DA at 25 yds.