jrbsr,

Other than the fact that the same steps in loading must be performed, there is not much simularity in loading the two cartridges.The .308 may be necked sized. Due to the "spring" in the actions the .30-30 is usually found in, unless a moderate load is being fired IMHO, the .30-30 should be full length resized or you may have a problem getting a lever action to lock up on a expanded case.

Due to the weakness of a lever action as well as the thiness of the .30-30 case, it should NEVER be loaded to the same pressures that are normal for the .308. Attempting to do so may earn you a new nick name, The Patch.
Even in bullet seating "difference" rears it head. With the .308 you can use any bullet, the correct diameter, and seat it just about any way you want. The .30-30 requires a bullet with a cannelure so the case may be crimped and then the design should be a flat nose bullet. Spitzer bullets are out unless your rifle is a two shot that carries one in the chamber and the second in the magazine.