I don't know if this is what you are looking for, but the Hornady website has a lot of ballistics info- www.hornady.com

For example, here are the ballistics for a 12 gauge slug (SST):

12 Gauge 300 gr. SST Slug [align=right]8623[/align] Velocity (fps) / Energy (ft-lbs) Muzzle 50 yd 100 yd 150 yd 200 yd 2000/2644 1816/2196 1641/1793 1482/1463 1341/1198 Trajectory (inches) Muzzle 50 yd 100 yd 150 yd 200 yd -1.5 2.4 2.7 0 -6.7
I couldn't find any charts for muzzleloading bullets on the website, but they do give the BC and SD of the bullets- for example the .452 300 grain XTP:
50 CAL SABOT WITH 45 CAL 300 GR XTP MAG BULLET [align=right]6726[/align] Diameter Weight Ballistics Coefficient Sectional Density .452" 300 gr. 0.200 0.210Looking on the Traditions website, they give listings for various bullets, powder charges & velocities. For example, the a 300 grain saboted bullet behind 100 grains of 777 will be 1700 fps. Then, you can plug that into the ballistics calculator on the Hornady site, and you'll get:

Ballistics Table in Yards300 grain XTP 300 gr., .200 B.C.www.hornady.comRange (yards)Muzzle50100200300400500Velocity (fps)17001536138911561014923855Energy (ft.-lb.)192515721285890684568487Trajectory (100 yd. zero)-1.51.10.0-16.7-59.2-134.3-247.5Come Up in MOA-1.5-2.10.08.018.932.147.3
I'm sorry this is kind of round-about - I'm sure one of the other guys will have something more concise for you.

But you can see that in this example, the 300 grain XTP drops more than 20 feet at 500 yards and is only moving at 850 feet per second or so. From that you can make a pretty convincing argument that a ML bullet is not going to go any farther than a shotgun slug. Unless someone is shooting in the air at a 45 degree angle, the ML bullet is going to hit the ground within 300 - 400 yards and if it is still in the air, shouldn't retain enough velocity to cause harm at more than 800 yards or so.

Hope this helps, at least a little!

(Sorry- after it uploaded I saw that the charts didn't translate well- I guess you'll need to go on the Hornady site yourself to look it up [:@])