Thought I'd pass along the info I've found. The gun was originally shooting low. I was wrong about that after further questioning the owner. Then the Combat Adjustible Kensight rear was added. Then it shot high. Seems the original front sight is the culprit. It was too tall for him as comes, then the adjustable rear rendered it too short as the Kensight rear at lowest setting is still taller than the factory Ruger fixed rear sight. The solution seems to be a new taller front sight paired with the adjustable rear.
I found this handy guide on the Kensight website.
FRONT SIGHT HEIGHT GUIDE
EXISTING FRONT SIGHT ALREADY ZEROED?
If you are only switching out an existing front sight and your pistol is
already zeroed, simply measure your font sight height from the top of the sight to the
top of the slide. (As shown in Figure 1) Use this same measurement to choose your correct sight height. If the exact size is not available, it is recommended that you use the next size higher and file the top of the front sight to reach your perfect zero.
SIGHT RADIUS MEASUREMENT
The
sight radius is the distance between the rear sight, and the front sight where the eye makes contact when referring to iron sights.
The sight radius measurement is always taken from the face of the front sight, to the back of the rear sight blade. (As shown in Figure 2)
IMPACT DISTANCE
The impact distance is the measurement of how far
off your bullets are impacting, from your point of aim. If you are aiming at perfect center and your grouping is either high or low, how far off is it in inches? If you are impacting
LOWyou will need a
SHORTER front sight. (As shown in Figure 3) If you are impacting
HIGH you will need a
TALLERfront sight. (As shown in Figure 4)
TARGET DISTANCE
The target distance can be based on just about any range. While 20 yards is a good distance to use, the industry standard is usually at 25 yards. The target distance will usually vary based on the pistol type (Target, Carry, and Compact Ect.) and shooters preference. The main concern is that you are shooting tight consistent groups before considering any changes to your front sight height.
THE FORMULA FOR FIGURING THE FRONT SIGHT HEIGHT
IMPORTANT: When using this formula, note that all numbers are figured in inches.
- Measure your Sight Radius.
- Multiply your Sight Radius times your Impact Distance
- Divide your Target Distance in inches.
Example: If your sight radius is 6.9” and you are shooting 2” low @ 25yds (900 inches) You will need to shorten your front sight by 0.015” (6.9” × 2” = 13.8” ÷ 900” = 0.015”)
FOR THE PERFECTIONISTS
If perfection is your goal, we recommend you install the rear sight and take the firearm to the range before purchasing your front sight. Whether you are just changing out just the front sight, or installing a complete sight set, you will have to know exactly where your bullet is impacting to figure for the perfect zero. You will need to have an existing front sight installed. You can try one of our recommended heights.
PRO TIP: To get the most range out of your adjustable sight, make sure the sight settings are perfectly centered. Turn the elevation screw until it stops. Now turn the other direction, count the clicks and divide by 2. This will be the perfect center of the adjustability settings. You can do the same for the windage adjustment if applicable. Next, take your pistol to the range and figure the above formula with the adjustable sight perfectly centered.
