Redback One has posted the zeroing standards from their Carbine Operator’s manual. Redback One is a wealth of knowledge so keep up with their latest posts on www.RedbackOne.com.
M4 Iron Sights
To adjust elevation using the factory M4 iron sights, rotate the front sight using a sight adjustment tool, multi tool or the tip of a bullet. To bring the point of impact up, follow the arrow markings on the front sight base. Up will be clock-wise and down counter clock-wise. Each indent or click on the front sight will move the Point Of Impact or (POI) by 1-inch at 100-meters.
To adjust windage using the factory rear A2 sight, follow the arrow markings on the right side of the windage knob. To move the POI to the right, turn the knob clockwise. To move the POI to the left rotate the knob counter clock-wise. Each click of the windage knob will move the POI ½ an inch at 100-meters.
Moving the Group
Following the manufacturers guide will give the shooter the best results when making adjustments to the sight during the zeroing process. The shooter must determine the center of the group or, the Mean Point of Impact or (MPI) before making any adjustments to the sight. The pattern formed after firing is known as the group. The center of the group is known as the Mean Point of Impact. If after firing the first three round group it is determined that the MPI is a long way from the desired zero point, the shooter should make bold adjustments, using the manufacturers guide to move the group in the general direction of the zero point. Once the shooter is in the vicinity of the zero point, he can then use fewer click adjustments to make fine movements of the group until the correct zero is achieved. Remember, the value of the click will be reduced by ¾ when zeroing from 25-meters. Therefore, if the value of each click is 1-inch of movement at 100-meters, the value of the same click will be ¾ less or ¼ of an inch at 25-meters.
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