I reload because I want to experiment with different bullet weights and configurations.
I have done some limited reloading for my SKS, but using expanding hunting bullets of weight similar to the military round.
I would be careful about using too heavy a bullet. All things being equal, a heavier bullet can cause pressure to build up quickly, which can cause problems.
When I reloaded for my SKS, the most difficult problem I had was finding a load that would provide both "accuracy" and "reliable cycling" of the gas powered semi-auto at safe pressure ratings. I only used two powders, but I feel that one of the powders would not have been safe to use for reliable action operation.
Be careful and good luck.