I bet that Lonshot would be good in this cartridge, but I have not loaded for this. I have loaded several in 45ACP with Longshot and have been happy with the results. I have been thinking of converting one of my 1911's over to this cartridge, 44mag power in a 1911 does sound nice, haha.
**MAXIMUM LOADS
Use EXTREME caution when handloading. Always start out below maximum published loads and work up from there. Eye Protection should ALWAYS be worn when reloading. All loading data contained within this web site is the result of testing by Johnny Rowland. This data proved safe in his testing. Clark Custom Guns, Inc. has no control over the components and equipment which may be used with this published information, no responsibility is implied or assumed for results obtained through its use.
Oddly enough my RCBS powder thrower meters 800X pretty well. I've seen the loadings for AA and LS for this round but have found 800X to work quite well in 357 SIG and 10mm. Two rounds where AA and LS are always shown. Of course, different cartridges, different powders. Perhaps 800X isn't a good choice for the Rowland. I don't know...
Well I don't load the Rowland but as we are talking powders and performance.
I use Accurate #5 in the 38 Super, the 45 acp and the 10 MM and find it extremely wells suited for those calibers if using plated/jacketed rounds.
Now I do NOT down load powder puff loads at all, if I shoot a 10 MM then I want to shoot a 10 MM, same with the 38 Super or 45 acp.
Accurate #5 produces good velocity, reasonable pressure and good accuracy for me, as to clean or dirty burning any powder requires a gun be cleaned so they are all dirty, but I find Accurate powders to be pretty clean burning, especially if you actually load the cartridge and not make baby loads.
All Accurate powders right now are impossible to find however!
hope this helps.
Sandi in Sharpsburg usually has AA powders. I bought some AA #9 for 10mm there sometime back. Haven't tried it for 10mm as Longshot or 800-X work pretty well, at least for me.