After setting either your windage or elevation and tapping either turret with your closed hand or a screwdriver handle . This done to seat the prism so the adjustment is locked down . Found this procedure when looking thru the paperwork of my brand new Trijicon #TA -31 RCO-M4CP 4x32 USMC ACOG also can't believe how crisp /clear the glass is and the reticle is very easy to read in any lighting condition . Also I like the TA-51 mount as it allows constant zero no matter how many times it is removed or re installed onto your AR
For what you pay for a ACOG it better be clear and crisp. Great scope just out of my price range for now.
When I have to make adjustments to my optics, I always try to tension the turret screw in the direction the manufacturer shows the adjustment. If. .I have to make an adjustment the opposite way, I will go beyond 3,4 clicks of what I need, then bring it back. Then I'll tap the turret. I find this sets, releases tension, what ever you want to call it. And zero, and adjustments stay truer.
I looked at the ACOG, but went with the M68 CCO. Might try an ACOG at some point, but as long as the M68 is working I leave it be. .
