Mine measured .125 tall & .117 wide. The sight should have a number on the bottom of the dovetail. If you are going to do this kind of work you NEED a dial caliper. Harbor freight, Northern, Sears all carry a "good" inexpensive dial caliper. My measurements may or may not be suitable for your gun. If you have not shot the gun from a rest yet hold off buying a different front sight. Shoot it stabilized in a rest( sand bag, roll of towels, etc.) before purchase. If it shoots POI=POA you are good. If not, you can compensate for any error with a different height front sight.