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............................ ..........Optics For Air Pistols..... .... . ... ..... ......By Todd Cooper

As a bit of a newcomer to airpistol optics I decided to do some research and testing of the various optical choices available. I found out some interesting details about pistol scopes that I was vaguely aware of but now I am fully aware. The problem which I encountered is NOT related to the scope manufacturer. This problem is very likely to be present with all pistol scopes which are designed for powder burning pistols. The problem is excess parallax.

To perform my parallax test I used a Nikko Sterling 2X pistol scope. This scope will focus sharply at short distances and everything will appear to be fine. I did not have to adjust the rear (eyepiece) focus ring on the scope and everything was clear at 18 feet, 33 feet and also at longer distances. The focus seemed to be set for my shooting eye. Focus should not be confused with parallax. Parallax is set at the factory to 100 or 150 yards on rifles scopes and typically 50 yards for pistol scopes. This means at 50 yards the scope will be parallax free.

For a handgun hunter with the scope mounted on his .44 magnum he is not worried about being 1/4" to 1/2" out at 25 yards or 75 yards because he will still make his hit. For an airgun silhouette shooter a 1/4" or 1/2" could mean a complete miss.

The pistol scope was mounted on a Beeman P-3 airpistol and sighted in for 10 meters. I propped the gun into a leather rabbit ear rest at this distance with a 1.25" black target bullseye at the pellet trap . The crosshairs were in the center of the black bullseye and the gun was rock steady. I then moved my head back and forth, up and down to see what would happen to the crosshairs. They moved about 1/2" each way! This is 1/2" from the center, each way. This is parallax and it can be a problem. Parallax is when the crosshair and the target are not on the same viewing plane. This means when you are not looking at the same angle through the scope for each shot the barrel will not be aiming at the exact same place. When shooting offhand it can be difficult to get an exact duplicate hold and head position for every shot.

For more information I decided to shoot some pellets to see if the parallax was really a true life issue. All shooting was done at 10 meters. First, 5 pellets were fired at the same bull with my head held as high as possible while still seeing through the scope. This shooting was followed by 5 pellets fired with my head held as low as possible while still seeing through the scope. The crosshairs were aimed at the center of the same target for all 10 shots but my head was in two different positions. I ended up with two distinct groups that formed a 1 inch total group. The test was performed again with 7 shots and I ended up with a vertical line of pellets that was 1 inch long. This shooting was with a gun and pellet combination that is capable of consistent 1/4" ragged holes at 10m when using an air rifle scope.

The kind of accuracy that I experienced with this scope is not what I want for shooting air pistol silhouettes at regulation distances . This scope would likely be parallax free at 50 or 60 yards but that will do me no good. 

Parallax is a fact of life with all scopes. If there is a decent pistol scope in existance which is designed for airpistols it will likely be set for parallax free shooting at 15 or 20 yards.

A normal pistol scope may work for someone shooting an air pistol for fun and not concerned with top accuracy potential. I would stick with iron sights if this were the case. As you have likely figured out I am an accuracy nut and would not be happy with not knowing if the miss was me or the parallax.

It is possible to shoot using the pistol scope while paying attention to head position and making sure the position is the same and the scope alignment is the same for each shot. This would be like shooting iron sights where you have to watch the front sight, rear sight and target at the same time. With the pistol scope you would have to watch the target, the crosshairs and the dark circle around the outer part of the crosshairs (inside scope tube). Not my idea of fun.

To add to my findings I asked a couple of airpistol shooters to check the parallax on their personal pistol scopes. One shooter has a Leupold 2X EER pistol scope which he checked at a 12 meter distance. This scope showed a total of up to 1.5" of crosshair movement. Once again, gross short distance parallax for a scope designed for powder burning pistols.

The next scope tested was a Norinco 2.5X pistol scope. The owner reported similar parallax problems when checked at close distances. Once again, a scope not designed with airguns in mind.

Next I looked into the popular red dot sight which is claimed by many to be parallax free at all distances. A wish that doesn't seem to be true. An article written by John Dreyer confirms the facts with a documented test on red dot parallax. John's test shows a parallax of 0.75" at 50 feet for the Ultradot model. The Propoint2 showed an error of 0.875" horizontally and 0.50" vertically. Once again this might not be something that would be desired for silhouette shooting.

Keeping the red dot in the center of the lens would be very helpful in reducing the parallax problem. When the dot is used at the sides of the lens that is where sighting error problems occur.

Another airgunner helped out with my testing and performed an actual shooting test using a Crosman 11ARD red dot mounted on his Beeman P-3 pistol. At a distance of 10 yards he noticed a definite vertical movement of his pellet group when the dot was used at the upper section of his lens. With a dot always centered in the lens he was able to keep all shots touching.

For more detailed information on red dot sights I encourage shooters to read the article at the following address: http://ourworld.compuserve.com/homepages/Dreyer_infonet/dotsight.htm

By now you are likely wondering what can be successfully used for optics on a silhouette air pistol. The answer seems to be an air rifle scope. Not all rifle scopes are designed for air rifles. A true air rifle scope will have an adjustable objective lens to compensate for parallax problems. The scope can be dialed down to distances as low as 10 yards for parallax free sighting. Using one of these scopes on an air pistol requires a special holding technique which most shooters find to be quite stable.

I would finally like to acknowledge the fact that Tim McMurray at Mac-1 Airguns provided me with some solid advice on optics for silhouette pistols.   Todd Cooper: