30-30 was the first rifle cartridge I reloaded for, starting in 1972. I always struggled with shoulder dimples until I started using Imperial Sizing Wax, and now it's the only case lube I ever use. I got my best accuracy results using Sierra 150 gr FP over 28.0 gr of IMR3031. Remember, with crimped bullets, it is critical that all your cases be trimmed to the same length or you will get damage to the case mouths when you seat/crimp.
Never try to educate someone who resists knowledge at all costs.
But what do I know?