Normally the easiest way to tell is if there are audible clicks when you adjust the scope. Friction adjustment scopes are normally inaudible. Did you ever hear of someone "slapping" their scope with their wallet?? They do this to seat the crosshair in the friction adjustment scope. Positive click adjustment moves the crosshairs the exact same amount with every click. Or otherwise known as "Repeatability".

This is a well kept secret in the scope world. It is much cheaper to build a friction adjustment scope. Some cheap scope mfrs. have even went so far as to add a "clicker" to their adjustment rings, but still have friction type adjustment. Tom.