skeeter 7MM

The eye relief is the max amount of distance your eye is from the eyepiece of the scope to obtain a clear picture (no black circles). This max. amount is determined by the manucaturer of the scope (ie: 4" or 5"). How you mount the scope to encompass the eye relief is based on your shooting position and is personal to that shooter. But basically set the scope so it is at the max eyerelief for your shooting positions by sliding it in our out inside the rings, before you clamp it down (the objective is to not have to move your head forward or backwards to obtain both eye relief and unobstructed site picture). One caution though if you have a variable scope with variations in eye relief that changes with power setting it is important to test it at higher power to ensure you do not get a black ring or require a head positioning that is a stark difference to your shooting style. Most guys will set it up at max power or lowest eye relief available to that scope therefore ensuring it always remain clear and is comfortable through the power adjustments. If a fixed eye relief or fixed power scope this point is moot!