Florida Flier,

Yes, there is no reason why you shouldn't be using lead. In fact, there are really few reasons why one would need to go with jacketed/plated. Probably the biggest advantage is that it is far cheaper and you will never wear out your barrel.

The most important thing to avoid leading is having bullets sized properly..... ie. 1-2 thou over your bore size. If this is right, hardness matters little at most paper punching velocities. In fact, as you mention, softer is better for modest loads because your bullet base will obdurate better.

By all means.... use lead. Even if you do get some modest leading.... it's easy enough to clean out with a brush and some copper scouring pads!