I have an old 336 SC in 35 Remington that was my Dad's. It has the microgroove rifling. When he got older and more recoil sensitive I started loading it with some 158 gr semi wadcutter bullets, that I had been casting for my .38 Special. The worked fine, were very accurate, at least at moderate range with the Lyman receiver sight we were using. Later I got a mold for a standard 200 gr gas check bullet for it, and have had good results for it.
I am not going to say it was shot a lot like this, maybe 20-40 rounds in a session, rather infrequently, then clean. We never had a problem with leading, and probably were hitting higher velocities with the 35 than you will with the 44 mag.
Like cwlongshot said try different levels of hardness, and velocities and if you can get a gas check bullet try those. I have a Ballard rifled 1894 Cowboy in 44 mag that leads easier than the old microgroove 35 Rem. Each gun is a story of it's own.