On Fri, Nov 25, 2016 at 11:02:44PM +0000, Bruce  Johnson wrote:
> figuring out range and such in a vacuum in different gravity fields
> could produce a lot of fun times.

In almost all cases, the maximum range is going to be vastly greater
than the effective range.  A rifle bullet on the Moon has a good
fraction of the speed needed to attain orbit, and unlike Earth it
won't slow down until it hits something.  Calculating the maximum
range would take at least a little orbital mechanics.

The maximum range would be on the order of a few hundred kilometres,
far beyond the horizon.  Even if they could see what they were aiming
at, it would be far beyond human ability to do so.

Even on a vacuum world with Earthlike gravity, the maximum range would
be tens of kilometres.

- Tim