Sighting In Your Gun

Sighting In Your Gun

 

Sometime around October every year every hunter wants to know how to get his/her gun sighted in correctly. Doing this correctly is less of a mystery than you might think and only takes a basic knowledge of ballistics and some attention to detail. This method will beat “hands down” the typical process of trying to get on the paper at 100yds, then adjusting the scope and wasting 3 boxes of ammo in the process.

The very first step is to make sure that the equipment is in good order. What this typically means is making sure that the rifle scope is properly mounted, all the fittings and screws are properly tightened to the correct torque specification, and that they are secured in place by blue Loctite or some other type of thread locker. The next steps are most easily accomplished by using portable target stands, such as the Hyskore 30291 Target Hound https://hyskore.com/products/30291-target-hound/, and also having the use of a stable bench or similar shooting platform, and a stable rifle support system. Two good examples of a stable rifle support system are the Hyskore 30105 Black Gun Shooting Rest  https://hyskore.com/products/30105-black-gun-shooting-rest/, and/or the Hyskore 30172 and 30173 Universal and Rabbit Ear Leather Rest Bags https://hyskore.com/products/rest-bags/. Now that we have the correct equipment identified, the first thing to do is set up your target down range from your bench. The Hyskore Target Hound allows you to use either 1×2 or 2×4 wood uprights, across which you would typically use a stapler to attach a piece of regular brown corrugated cardboard roughly 24”- 30” wide and 36”- 48” high. You, of course, can use any type of target. There are two cross targets that are extremely good that can be downloaded from the Hyskore website https://hyskore.com/wp-content/uploads/2015/06/30018_Target_8.5×11.pdf. https://hyskore.com/wp-content/uploads/2015/06/30022_Target_11x17.pdf. Another choice for instant visual gratification, one of the sight and see type targets, which leave a bright visible mark when a bullet makes penetration.

Now the quick ballistics education. The line of sight through the scope to any target down range is a perfectly straight line. The bullet, on the other hand, is affected by gravity the instant it leaves the muzzle. As a result, the trajectory is a curve. The very first point where the path of the bullet crosses the line of sight is known as the near zero. Coincidently, the second point down range where the path of the bullet crosses the line of sight is known as the far zero. The elevation settings for both points are exactly the same. Typically the near zero for a high powered center fire rifle, firing a bullet at 2700-3300 ft. per second, with the axis of the scope mounted 1.5” over the axis of the bore, is about 27 yards. This could vary +/- a little bit depending on the velocity of the bullet. For all intents and purposes, 27 yards is a good distance to work with.

Now that we have the details worked out, the next step is to fire a shot at the 27 yard target. Since we are only 27 yards away, no matter how poorly aligned your scope is you are still going to get on the target, which is of course what we need so we have a data point from which to make the necessary adjustments. The objective being for the bullet to end up striking dead center on this target. Typically the shot will be either a little bit left or right and probably a little high, because the bullet is still ascending at this range. Keeping in mind that your typical scope has ¼ MOA (Minute of Arc) adjustments and when we check our quick reference guide we realize that 1 MOA is equivalent to 1.06” at 100 yards. With this knowledge we are now able to make the necessary calculations to move the point of impact to be coincidental with the point of aim, which of course is the dead center of the target. Since our range is approximately 25% of the distance to the 100 yard target, it will take 4x’s the number of clicks to move the point of impact 1”, as opposed to the 4 clicks it would take at 100 yards. In other words, if you are 1” high, you will need to adjust the scope elevation down by 16 clicks. You will find that moving the point of impact around at 27 yards is relatively easy because you are already on the paper and everything is right in front of you. Once you have been able to confirm dead center hits, it’s time to move on.

The next step in the process is either to have an additional portable target stand at 100 yards, and/or move your existing target stand out to exactly 100 yards, and replace the target with a clean one. Now fire a 3-5 shot group from the original firing position and note where the point of impact is. Typically it will be a little bit high, for example, maybe 2”. Now you need to get to the record keeping part of the process, which is absolutely necessary because what we are going to do is create a range card, which is going to give us the come ups for different distances. You also need to know exactly the type of ammunition you are using, the bullet weight, the manufacturer, etc. as if you change to heavier or lighter bullets, obviously the point of impact will change and you will need to redo the exercise and develop new data. Therefore, take note of the exact distance up or down from the center of the bullseye to the point of impact, and then (for example) move the target out to 150 yards, repeat the exercise, then to 200 yards, repeat the exercise, etc. Basically you want to be able to define where the bullet is going to hit elevation-wise at the range you typically hunt. You want to record this data and then create a small file card with this recorded information and tape it to your buttstock with clear waterproof tape. This way you will be able to quickly reference the information when you are in the field and make the necessary point of aim adjustments so that your point of impact and point of aim will be coincidental, and you will be spot on. Your rifle will be perfectly sighted in.