Swanny, you're question is too general to precisely answer for you, but there are ways you can figure it yourself.

First you need to know the BC of the bullet you are using, next the muzzle velocity. After that, go to: http://wildcatshooting.com/ballistics/ , plug in the values and calculate to your heart's content.

Here's a thing or two to consider. Sight height has an influence on this, are you using a scope? For the velocities of the 30-30 a 3" PBR will be fairly close with factory ammo. If you're shooting handloads for a single shot or bolt gun and use spitzer bullets it will be a bit farther. The 30-30 is a fairly short range proposition in the best of circumstances, it is intended primarily for hunting smallish to medium sized big game, and as such a 5" PBR will serve for deer sized game. Without checking the details I'd suggest that 150 yards is as far as you want to go with factory ammo in the 30-30, spitzers might get to 250. I sight my Model 94 1.5" high at 50 yards for dead center(+/-) at 100, using 170 gr Hornady FN. The TC Carbine is 1.5" high at 100 meters for about dead on at 150 with Rem 150 Core-lokts. With 150 gr. Sierra Spitzers and RX15 it's 2.0" high at 100, on at about 175. That's fairly close to answering your question but I do not know what you're shootin'. Hope this helps.