I think Leer said something about why it was changed so long ago. Something about so many revolutions until the round detonated. But, I wouldn't mind seeing it again either. ACs, barring the new changes coming, are gonna be slower than even the slowest energy weapon (ppcs come to mind), so if you're willing to waste the ammo/damage on a far off target you're "pretty sure" you're gonna hit; I say why not! More tactical choices for the player.
However, now, I don't know what the technical ramifications of such an infinite ranged ballistic would have of the mods performance. Nevertheless, old long range AC's get a +1 from me.