Well, I am not familiar with the Colorado law on such a matter but I also have about 35 acres of mostly trees, hills, cactus, rocks etc., well out of town and I have been shooting on my property since about 1995 when I moved out here from that shit hole known as the State of Illinois. Out here we have covenants covering a few things and one of the very few "restrictions/suggestions" is that no one is allowed to do or have things that will annoy fellow neighbors. However, almost all of my neighbors have firearms and I have yet to hear ANY complaint about my shooting. Of course, I rarely ever shoot anymore and if/when I do, it would be very late morning and early/late afternoon times so as to not be bugging or waking anyone up with the sound of gun fire, (probably considered noise to any non-shooters).
If I do/did ever receive a complaint, I'd sure politely/diplomatically talk with the complainant and I'm sure everything would be just fine from that time on.
Will be interesting to see what BrokenScout will add to this!