I am not too familiar with scopes but I have a Colt 3x20 scope that came with a rifle that I purchased that seems to have problems. No matter how much I turn the windage or elevation knobs, the cross hairs inside the scope do not change. I removed the screw on the left side of the scope and the crosshairs became tilted, so I take it this just keeps the crosshairs straight. I also notice that there are adjustment knobs under the adjustment knobs, the top one has an arrow on it and says up and one on the right side has a curved arrow and what looks like crosshairs and these are to get the crosshairs where you want them to and use the outer knobs to fine tune, correct? So why don't the crosshairs move with the adjustment knobs?

Hakko of Japan manufactured Colt scopes for a long time. Excellent quality ground lenses and the mechanical design is bullet proof. The top turret has a BDC built in. Simlpy zero and then adjust the turret as you engage targets further out.

To adjust the scope for zeroing you must first remove the dust covers off the top and right turrets. Actualy the top is technicly the only turret but I will refer to them as both. After the dust covers are removed you can see the adjustment dials. You can use a dime or a screw driver to do this adjustment.

Make sure your top turret is at the 100yd mark. Turn the turret to hear and feel the "click" ensuring your scope is indexed correctly. Now you can zero at 100 yrds.

The reason the reticle does not appear to move during adjustments is because it is a one piece reticle. Adjustments are done internaly with a series of lenses.

Do not remove the left or bottom screw covers. As you found out these hold tension on the internal adjustment mechanics. Also you have purged the nitrogen enviornment necessary to keep condensation from forming inside your scope.

At the factory most scopes are dry air purged and pressurized slightly to keep the outside moisture from entering a scope. So on varying temperature day you wont get moisture forming on your lenses or corroding the internal mechanical design.

Great scope you have and one designed to offer many years of shooting accuracy. Visit the Marylands web site that Forest offers to all for the sight in procedure of your scope. Plus it has lots of other great info for us shooters.