Weird parralax adjustment knob on my scope..?

That is odd. I have only seen one of these in person, and it had graduated marks with numbers like the one on this website. a href="http://www.snipercentral.com/menace4.htm" rel="nofollow"http://www.snipercentral.com/menace4.htm/a A picture might help us out, otherwise just adjust it to the distance that allows the scope reticle to be clear at the same time your target appears clear. I tried to answer your question, but you really didn't have a specific one so this is about the best I can do.