Every rifle user who heads into the field for the purpose of hunting has the moral obligation of having his firearm properly sighted in. Whenever the opportunity for a shot on a game animal arises, there are often other elements that may decrease our chances at delivering the all important fatal shot. Some of these elements are the strength and direction of the wind, distance to the target, our level of excitement and physical exertion at the time of the shot and if the shot is uphill or down hill. We do our best to control or allow for these variables by determining the distance with a laser rangefinder, using a steady rest and allowing for the wind and angle of the shot. What we don’t need is the possibility of wounding or missing a game animal because our rifle is not properly sighted in. Sighting-in a rifle is not very time consuming, difficult or expensive if we have the proper equipment, and follow some simple steps.
The first step in sighting in a rifle is to attach a durable, high quality scope. Don’t skimp in this area because your gun can only shoot as good as the scope will allow. If you’re mounting a scope on a rifle for the first time, use Thread Locker or Loctite on the screws and torque the bases down until they’re quite tight, but don’t over do it. Attach the Laserlyte boresighter level to the bases and level the gun by centering the bubble in the level, then secure the gun in this position so it can’t be easily moved. The rifle will have to be within a few feet of a wall because in a later step, you’ll be projecting a laser beam which will be used to level the scope. Now remove the leveler and attach the rings and scope according to the manufacturers instructions. Be careful to keep the tops and bottoms of the rings matched, as they come from the factory, to ensure stress-free alignment with the bases. Adjust the scope to get the proper eye relief but don’t tighten the ring screws just yet.
The next step in sighting in a rifle is to insert the Laserlyte laser boresighter into the rifle’s muzzle and attach the bubble leveler and turn them until the bubble indicates they are level. Now tighten the boresighter in this position by turning the tightening collar. When you turn the laser boresighter on you will see a horizontal line projected onto the wall. Look through the scope and adjust the reticle by turning the scope until the horizontal reticle matches the the horizontal laser line, then tighten the ring screws. Your gun and scope are now perfectly level with each other. Remove the bubble leveler. You’re now almost ready for the boresighting step.
Before you go to the shooting range, you’ll want to determine the best range to sight-in your rifle. If your rifle will be used only for shorter distances, you may just want to sight it in for 100 yards. But if it will be used for long range as well, you’ll want to sight-in for a longer range to best utilize the rifle’s trajectory. A good system to use is the MPBR (maximum point blank range) system. It’s a system of sighting-in that allows the hunter to aim dead on out to the MPBR and be ensured of a hit to the vital zone of the game animal without holding over. When sighted-in with the MPBR system, the amount the bullet rises the highest above the line of sight is the mid-range trajectory and the amount that the bullet falls below the line of sight that same amount is the MPBR. Most big game hunters use either three or four inches as this amount. Varmint hunters may want it to be two inches or even 1.5 inches. The range where the bullet and the line of sight meet, is of course, the sight-in distance. Once sighted-in this way, the hunter limits his shots to within the MPBR and just aims dead on. If shots are kept within the MPBR, the bullets will stay within the vital killing zone of the animal.
There are two ways to find the MPBR for your specific cartridge. The first is to take a look at the trajectory tables for your rifle/cartridge combination and the second, and more exact way, is to use a bullet ballistics program such as from Barnes or Sierra. With these programs you’ll be able to enter the specifics of your cartridge such as bullet caliber, weight, ballistic coefficient, velocity, and a lot more plus the mid range trajectory amount you choose to use. The results will show the rise and fall of the bullet above and below the line of sight at all practical shooting ranges as well as the sight-in range. Take note of the rise in trajectory of your load at 100 yards and the sight-in range, then head to the shooting range.
Once your at the shooting range you’ll need a shooting bench or other type of steady support with front and rear shooting rests. Place the target at 25 yards and support the rifle on the shooting rests with the boresighter laser projected onto the target. Adjust the reticule until it’s perfectly matched to the center of the laser spot. Your rifle is now boresighted. Remove the boresighter and fire a shot at the target. It should hit very close to the bulls eye. If not make the corresponding adjustments to the scope. Now place the target at 100 yards and fire one shot. At this distance you want the bullet to hit directly above the bulls eye the amount you determined from the ballistics tables or ballistics program. If it didn’t, adjust the scope and fire another shot and repeat until it does. Once the shot is hitting where it should, fire two more shots to make a 3 shot group. Determine the center point of the group 17 wsm Ammo for sale and adjust the scope, if needed. Continue firing 3 shot groups and adjusting the scope until the groups are printing exactly where they should. If your shooting range is long enough, you may now want to move your target to the sight-in distance and shoot a group to verify that is is hitting dead on. If it is, your rifle is now sighted-in for the bench position.
I like to take the sight-in process a couple of steps further. I shoot at 100 yards from the sitting position using a set of shooting sticks. Most times shooting this way, I’m able to keep my group size almost as small as from the bench. If the groups I shoot from this position are a little off, I adjust the scope so the rifle is shooting right on. Only now do I consider my rifle truly sighted-in. But I’m still not ready to go hunting yet. I like to make 2 or 3 more trips to the range to shoot on targets from field positions such as sitting, kneeling and standing. These shooting sessions are always very rewarding. They show me exactly how far I’m able to consistently hit a certain size vital zone from field positions and I then limit my shots to within those ranges while hunting. I also practice rapid fire shooting on targets from the standing at 50 yards. While hunting, it’s sometimes necessary to make follow up shots, and this practice teaches me to not hesitate, and to make fast and accurate shots.
After my rifle is sighted in, I go back to the bench and place a target at 25 yards and use the boresighter to project a laser beam directly onto the bulls eye. I mark where the cross hairs are on the target, then whenever I go hunting, I take this target and my laser boresighter with me so I’m always able to use them to check that my rifle is still sighted-in, without firing a shot. It’s an important consideration when my rifle has been riding for a while in a bumpy hunting vehicle or after it takes an accidental knock.