33.8-37.5gr AA-1680 with a Sierra 240gr JHC....I used 37.0gr
28.8-32.0gr AA-1680 with a Sierra 300gr JSP.....I used 31.0gr
this is in an M7445-10HV.....sold the revolver because I simply got tired of the recoil. Wish I hadn't now with the prices the way they are.
BTW, Starline stopped making the brass, but it can be made from .303 British or .30-40 Krag. A .44 caliber case made from cutting the .30-40 Krag off at the shoulder for a 1.75" case length is called the .44 Rhino. Despite claims to the contrary, brass cannot be made from the .444 Marlin. The .444 is .470" above the rim, the .445 is .458".
(Data is from Accurate Arms #2, pg. 136.)