You have a big buck in your crosshairs, a stable shooting position, a buttery smooth trigger pull, but when the shot’s smoke clears, that buck is still standing defiantly. What went wrong? Most likely, it was an improperly sighted rifle scope, and few things can be more detrimental to your hunt. No matter how amazing of a rifle scope you have, if it isn’t sighted in properly, it’s just a useless piece of glass. This simple guide to sighting in will help you get back on target and filling tags in no time.
Check the Mount
Before you get down to the sighting process, you’ll want to check that the scope is mounted properly. No matter how many bullets you put towards the paper downrange, if the scope is mounted incorrectly, your rifle will never be sighted in correctly.
Start by checking that you’re using the correct scope rings and that they fit tightly. If there’s any wiggle room after tightening, you’ve probably got the wrong rings. Next, look to see that the rings are securely mounted to your sight rail. This usually isn’t a problem, but they should be tightened periodically and especially if it has been in transit recently.
Set Up a Steady Shooting Position
For your rifle to be sighted in perfectly, it needs to be in the exact same position after each shot. Many shooters will use a gun vise like the one below to keep their rifle steady. If you don’t feel like spending more money on gear, setting up on a couple of sandbags is sufficiently steady if you’re careful.
Know Your Loads and Distance
All of your efforts to sight in your scope will really only make it accurate with one particular cartridge load and at a specific distance. Fortunately, this should be only a minor inconvenience. Unless you’re sighting in with bargain brand cartridges and then using some really exotic loads for hunting trips, you should only see a small difference in shot positions and it’s somewhat predictable. All things being equal, hot loads travel faster and heavier bullets slower; adjust your reticles vertical axis accordingly to account for bullet drop. As for distance, you’ll need to aim higher the farther out your target is (get a rangefinder!). If you know the velocity of your bullet, you can do some calculations that will tell you how much adjustment is needed at different distances.
Get Shots on Paper
Before you can start zeroing in you need to make sure that the barrel of the rifle and the scope are actually lined up correctly. The easiest way to do this is with a laser bore sight; it’s essentially a laser pointer that fits in the end of your barrel. Aim at the target and you should see a little red dot on it through your scope. Now make adjustments on the scope until your crosshairs are over the red dot. It’s best to do this step at close range, about 25 yards, to ensure wind and gravity don’t have a noticeable effect on your bullet’s trajectory.
Now remove the bore sight and take a shot. If it’s on the paper, you’re ready to move on to fine tuning at larger distances.
Make Small Adjustments
You’re on paper, it’s time to start moving back to the distances that would be useful on a hunt. One hundred yards is the standard, and at that range your bullet drop shouldn’t be so severe that you’re off the paper from the bore sighting.
Again, get yourself in a steady shooting position, take a deep breath, exhale half way, and slowly pull the trigger. Take a look through your scope and see how far off target you are. It’s probably not more than an inch or two, and it should only take a few more shots and a couple turns on the adjustment knobs to get it perfect.
Keep Your Shots Clean
This is one of the most annoying aspects of sighting in a rifle. If you need several (or a couple dozen) rounds to get it sighted in correctly, chances are the barrel will get a little dirty. Every ten shots, it’s a good idea to clean out the barrel. If you don’t, the scope will be sighted in to the specifications of a dirty barrel. It’s also a good idea to let the barrel cool down after several shots as it can heat up and warp ever so slightly.
Check, Check and Recheck
No matter how much effort you put into sighting your rifle scope, something can always go wrong. Maybe you drove over a big bump and the rifle got jostled a bit too hard in its case. It’s always a good idea to check your scope one last time before starting a hunt. As annoying as this might be, it could prevent a miss later on in the day. Another important consideration is if you add any accessories after sighting in: bipods, heat shields, and anything that might throw off the balance of the rifle.