This might be a silly newbie question, but why are there no range adjustable sights from Aimpoint or ACOGs?

I ask because the stock A2 sights seem like an elegant solution- sight in the weapon once and dial up the range to target when needed. Does this system work as well as it's supposed to?

It strikes me that having an extra knob on an Aimpoint or ACOG would be easy, with light weight detents every 25 meters and stronger detents every 100 metres. With the right manufacturing techniques, these guys could even set CNC lathes to automatically mill out custom calibrated adjustment screws for various bullet weights, barrel lengths and powder.

And for precision shooting or sniping, wouldn't such a system be easier then dealing with 1/4 MOA clicks in the field? Your spotter tells you the range, you click the knob to that range and shoot. I think US Optics does something like this, but I AM a newbie to the whole shooting thing, so this all might be a single, large, dumb question.

What he said.

If you have time to fiddle with range adjustments during combat, well...........  good luck to ya.

If  you do have time, you'll need a lot more than a 4x ACOG - start looking at 10X sniper scopes.

What they said.

If you sight in your Aimpoint at 50 yds, you will be within 3-4 " POI all the way out to 250, which is about its useable range.  The built-in BDC of the ACOG allows the adjustment you are taking about without loss of zero by truning knobs.