I had a 5moa red dot on a rem 597 in .17 hmr and shot gophers reliably to 130 yrds with a fellow with a scoped .22 mag...i could easily run with him to those ranges and probably even a little better. Red dots are pretty handy sights...very fast and if the gun is accurate then the gun is accurate...nuff said there.
A bit of a trick to zero it though. I used large black circle targets at 100 yrds and centered the red dot in the circle for shooting and i moved the group around inside the dot until i was happy that it was centered and that anything i put the dot over would get splattered...and it worked as planned.