Zeroing your Scope

Today is the day. After months or even years of research, you finally did it. You just bought the precision rifle of your dreams with the glass to match. Now what? Before you can start putting rounds through the same hole you need to zero your optic to your rifle. The process is simple, but if done incorrectly, can cause misses, confusion, and frustration. Fortunately for you, I’m here to explain the process and get you shooting ragged holes in no time.

The SRS A2 Covert

For me, that dream rifle was my Desert Tech SRS A2 Covert in .308 Win. The scope I mounted was the Vortex Gen2 PST 5-25X50. It uses an MRAD reticle, so we’ll be measuring in mils. If your scope uses MOA, your values will be different, but the process is the same. I’ve been wanting one of these rifles since I was a kid. I guess you can say I’ve been researching this acquisition for close to two decades! Caliber-wise, there are more modern, flatter-shooting calibers than the .308, but it’s a workhorse round, and that mates well with this workhorse rifle.

Ammunition prices being what they are, I had to settle for something a little less precise than I would have liked.

I want to take a quick moment to define some things for those who are new to shooting; especially those just starting long range. In the simplest of terms, zeroing your rifle means that you’re making adjustments on your optic in order to make sure that your rounds impact (Point Of Impact or POI) exactly where you’re aiming (Point Of Aim or POA). We do this by adjusting two measurements. Windage refers to lateral movement. Elevation is the opposite and refers to our up and down movement. To accomplish these changes, we turn the turrets that sit on the top and side of your scope. These turrets should click as you turn them, giving you positive, tactile feedback, so you know how much of an adjustment you are making.

After the scope has been properly mounted and level, it’s time to get this thing on target. What range you zero your rifle at is as personal as which side you’re on in the old boxers versus briefs debate. Depending on what you plan to do with a firearm, the zero can be very different. For example, I have an EOTech XPS3-2 on my F-1 Firearms FDR-15. For that rifle’s purpose, which will likely be shooting between 25 and 300 yards, I use a 36 yard zero. It provides the most versatility and margin of error for me at those distances. Some people who know most of their shots will be at 250 yards or beyond might choose to zero at 250. For our purposes, we’re gonna stick with the good ol’ 100 yard zero.

After deciding our range, we need to get into the most stable shooting position we can. Whether you use a bench or just get on the ground doesn’t matter, so long as the gun isn’t moving around. I ended up going prone. I was on a wooden platform and laying on a shooting mat.

Find your target, load a round into the chamber, disengage the safety, and let one rip. After confirming that there’s a hole in your target at all, send another two rounds, trying your best to put those rounds as close together as you can. We want a tight group so we can more easily determine what our scope adjustments need to be. Here, the point of aim was the center of the bullseye. Ignore that top hole. I was pretty lucky that the POI was already pretty close to the POA, but your mileage may vary.

The better the ammunition you use, the more precise your POI will be

This is where we start to dial things in. Find the center of your group and measure its distance from your point of impact. You can see that my first three rounds impacted 0.4 mils right and 0.3 mils high. Since we’re 0.4 mils to the right, we need to adjust our windage. Each click on this scope is .1 MILS. That means we need 10 clicks to equal one mil, or 3.6 inches at 100 yards. We need to move 0.4 mils, so we’re going to click four times to the left.

Now that we have our windage adjusted, let’s fix the elevation. The click value is the same, so to bring the point of impact down by 0.3 mils, we need to turn the turret three clicks to the left. 

With these adjustments made, your next three rounds should be close. Slowly and deliberately send another three rounds. If you’re not dead on, you should still see your group landing closer to your point of aim than the last group. If this is the case, simply repeat the process until you’re hitting exactly where you’re aiming. This was the second three round group.

This isn’t the best representation of the SRS’s accuracy, it generally shoots .5 MOA with Match ammo

The rounds still weren’t impacting exactly where they were aimed. Elevation was on, but POI was off 0.1 mil to the left. After one more windage adjustment of one click to the right, she was dead on. Since the gun was grouping consistently and ammo is expensive, one more round was enough to make me confident that the zero was money.

You are now officially zeroed and ready to do some work. I’m borderline cheating because of the accurate nature of this rifle. The match trigger on the SRS A2 Covert isn’t hurting either (trigger snobs, be warned. This thing will make you question everything you thought about bullpup triggers).

Establishing and maintaining a proper zero is incredibly important, especially as you start to push the capabilities of your platform. Your zero is the base measurement from which you will calculate your point of impact at closer and farther distances. If you’re using this rifle to hunt, a true zero can mean the difference between dropping an animal where it stands, wounding it, or even going home with nothing to show for your efforts. There are varying opinions on the best range at which zero and how to achieve it. This is simply mine. If it doesn’t work for you, find a method that does, there is plenty of information on the internet on the subject.

There are so many factors to consider when shooting for accuracy. Barrel length, twist rate, bullet weight and velocity, and more. Your zero is just the first step. Take your time, do it right, and above all, be safe and have fun.

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