Well, I took my new M1A out yesterday, and found the darn elevation knob wouldn't stay dialed in.  I blame it on having took out the elevation knob screw out earlier that day and having not put it back in tight enough.

So, I've gotten the thing about as tight as I could get it tonight, only to find that adjusting, especially lowering the aperture from its highest point, is a real chore now.  So, I've loosened it ever so slightly.  Is that good enough, or does it need to be cranked as tight as humanly possible.

I've also noticed that on the side of the elevation knob facing the sight base is quite uneven.  At the 2 mark, there's a little tip on the knob.  Sometimes I'll turn the knob and not even hear an audible click.  Is all this normal?  

To tension the elevation you tighten the lock nut (1 or 2 clicks as needed) on the windage knob------

The elevation knob calibration screw is tightened enough to lock the internal indexing tabs to the face of the pinion--------- It doesn't need to be super-smoked down-----

The detent on the elevation knob contacts the serrations on the receiver. This is what gives you the "click" when adjusting the elevation. What tensions this is the springloaded lock nut on the windage knob-------

I'm almost starting to wonder if there is some more user error on my part here.  I've read the handout that comes with the  M1A thorougly.  As I understand it, the elevation knob on the M1A works exactly the same the elevation knob on the AR-15.  

Exactly what is the point of being able to unscrew the elevation knob?

Any help is appreciated...

Quoted: I'm almost starting to wonder if there is some more user error on my part here.  I've read the handout that comes with the  M1A thorougly.  As I understand it, the elevation knob on the M1A works exactly the same the elevation knob on the AR-15.   Exactly what is the point of being able to unscrew the elevation knob? Any help is appreciated...

To be able to calibrate the elevation.

IE-----set the elevation knob in relation to how many clicks needed to get the desired zero.

Is it absolutely necessary to unscrew the windage knob, or can I just count the clicks?