There are NOW 14 different Beartooth 44 bullets, 4 of them are dual crimp (18 C.O.L. combos). I am in the process of testing these (don't have them all yet) in the 444 Marlin and 44 Mag Handi's. But in my past experience, it is rare that I found ANY leading. But I do keep all load development pressure ranges between 28,000 PSI and 29,900 PSI, suppose be be the idea PSI range for 21 BHN cast bullets. Don't have any idea if this is true but loads are not max loads so what is the harm in testing, besides really cuts down on the combinations of different loads to test.
But in the past, my 444 marlin has been very accurate with almost everything I feed it.