There was a similar comparison made a few years ago, before the Colorado Wildlife Commission, as to why sabots and pellets should be outlawed in the regular muzzleloading season. They were primarily concerned with elk and the current season structure that allows muzzleloading hunters to engage them at the peak of the rut.

If you run the numbers with loads in the 2,000 plus fps muzzle velocity, the .50 caliber looks real good compared to the .30-30. Particularly with spitzer bullets like the T/C Shockwave, that has a ballistic coefficient about as high as the 150 grain .30-30 bullet.