Range Finders for the Airgun Hunter
The most important factor for harvesting/hunting small game with an air gun is shot placement. The outcome of long distance shooting is significantly improved with the use of a quality scope and a range finder for the precise shot placement required for quick clean kills (head shots). Range estimation is especially important when using larger caliber springers or when the power output through a PCP is limited, because in these guns the flight trajectory of the pellet will be more arced. Most of use are pretty good at making gross observations of distance; is an object close or far away. However, telling whether an object such as a plump bunny is sitting thirty or forty yards away invarying field conditions is somewhat more difficult. If you hold the crosshairs on the rabbits head at thirty yards you will hit him in the head, while with the same hold on the rabbit at forty five yards you will end up shooting him in the belly. Because of the importance of ranging your shots accurately when hunting with an airgun, many hunters either use scopes with a AO correction and mil-dots or carry a laser range finder to be sure of distance. Laser rangefinders work by sending out a beam of infrared energy that will reflect off the object it's aimed at. A high-speed internal clock measures the time it takes the beam to return and calculates the distance based on that information. Since the propagation velocity of the transmitted signal is known, it is a relatively simple operation for the onboard computer to work out the distance. How well they work depends on the reflective properties of the target, as well as environmental conditions. Color, surface finish, size, and shape of the target all affect performance. Highly reflective surfaces or colors are easier to "read," and a small target is harder to read than a large object. A target that is at a 90 degree angle to the laser is better than one more angled. Overcast days will provide longer-range readings than will bright sunlight. Using a rangefinder effectively during your hunts will require a learning curve. If you simply carry it around in your pocket until you see a distant rabbit and then try to measure the range you will likely be disappointed in the results. The units will read off the hair of big-game animals, but it's not a great surface, and small game animals will not register. The work around is to pick a hard object close to the critter, such as a rock or a tree, and read from that. It's also a good idea to range several landmarks when you first reach your stand so you can reference them when an animal arrives, as there is not always time to recheck the distance. When squirrel hunting from a blind I’ll measure out the distance between myself and nesting trees or food sources in the area, so I’m ready to play when the squirrels come out.