I have seen the following words to describe bores: "cylindrical," "conical," "tapered," "step," and maybe one other. I know what the first two mean, but what are the other two? And what effect does the shape of the bore have on the sound and response? One more thing- when we see the bore measurement ie: .464, what is the unit? Centimeters? I assume that these have already been addressed on other sites (and probably here too), but I figured it would be good to have the information all in one place, so myself and others can refer back to it. Thanks!