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G&A Basics: How to Zero a Rifle in Five Steps

by Craig Boddington   |  November 12th, 2012 20

004_Cold-and-CleanIt doesn’t matter whether you’re going hunting or planning a fun day at the range; you want to hit what you’re aiming at, so the first step is to make sure your rifle is properly zeroed. Here’s how I do it:

1. Get on Paper
If your rifle is an old friend, this step may have been handled long ago, but if it’s a new rifle or you’ve changed scopes, then the first thing you must do is get the rifle on paper. In order to do this, you must get your barrel and scope (or sights) in rough alignment. A collimator or laser boresighter will enable you to do this quickly, and these devices are really the only option for actions (semi-autos, levers and pumps) where it’s not possible to look down the barrel from the breech.

With bolt-actions and single-shots, I generally achieve rough alignment by boresighting. Remove the bolt, or on a single-shot, open the action and set the rifle in a solid, steady rest. Put up a target at short range—25 or 50 yards. A bull’s-eye target is probably best for this because it’s easier to align the round target within the round view through your barrel. Line up your barrel on the target, make sure it’s steady and then look through your scope or sights. Using the adjustments, move the scope or sights until you’re seeing the same “picture” as through your barrel.

Now it’s time to shoot. I’m pretty darn good at boresighting, and once in a while I get it spot-on—but it is not a perfect science, and neither collimators nor laser boresighting devices are perfect, either. So I start with a big, clean target! If you have some confidence, you can start at 50 yards, which is what I usually do—but if you’ve just clamped a scope on something like a lever action, where it’s impossible to look down the barrel, better start at 25 yards with plenty of clean target—sometimes you can be way off! Shooting and making adjustments, I try to get the rifle more or less zeroed at short range. The legend is that a 25-yard zero will be about right at 100 yards, but this is not true. It depends on the trajectory of the cartridge and the height of the scope, but generally speaking, a perfect zero at 25 yards will be too high at 100 yards, so if you start at 25 yards with a scoped rifle, you’ll usually save some ammo by making that initial short-range zero about an inch low. When I start at 50 yards I try to make it “point of aim, point of impact”—and then I’m ready to move out to longer range.

2. Make Your Decision
Now that the rifle is roughly in zero, there are three basic decisions to make before fine-tuning: distance, load and point of impact. For distance, I believe in zeroing at 100 yards. Less is not precise enough, and while I know some good riflemen zero at 200 yards and more, I prefer to sight in at 100 yards so I remove as much human error as possible and minimize effects such as wind. If you plan to shoot at longer ranges, it’s a good idea—and maybe essential—to practice at longer ranges, but for sighting in, I prefer 100 yards.

If you’ve already decided what load you intend to use, then you’re ready to move ahead. But all rifles display different levels of accuracy when you change brands, bullets, propellants or anything else. So if you’re still working on what load you want to use, I recommend postponing achieving a perfect zero and just shoot groups. At this point it doesn’t matter where they land on the target. You may ultimately select the most accurate load that you try, or you may compromise a bit between optimum accuracy, bullet performance and even velocity.

Once the load is selected, you need to decide exactly where you want your 100-yard point of impact. For short-range hunting situations—like close-cover hunting or for dangerous game—you may well want a 100-yard zero. For shooting at longer ranges you’re probably going to want your point of impact to be a bit high. I like a zero that’s maybe 2 to 2.5 inches high at 100 yards. Depending on the cartridge, this will put me dead-on at maybe 200 to 225 yards. These days, with long-range shooting all the rage, a lot of guys sight in to be 3 inches high at 100 yards. That’s your choice, but the mid-range rise may exceed 5 inches, and the most common aiming error is to hold too high rather than too low, so as Jack O’Connor advocated a generation ago, about 2.5 inches high at 100 yards is just fine.

3. Use Good Technique
Sighting in is just like shooting groups—it has nothing to do with how well you can shoot; it’s all about the rifle, so you want to eliminate human error. Use a good, steady rest, and take your time. The bench accentuates recoil, so don’t hesitate to pad yourself or use recoil-absorbing shooting aids like the Caldwell’s Lead Sled. Settle down, really concentrate and squeeze the trigger, and then adjust your sights and do it again until you have reached your desired zero.

When I’m shooting from a bench rest, I try to get the rifle perfectly steady, and I let the sandbags or rifle rest do the work. I use my supporting hand to snug the butt into my shoulder, with my trigger finger the forward-most contact.

4. Cold and Clean
If you’re lucky you might get the rifle “pretty close” in three or four shots. Sometimes it takes quite a few more! Relatively few riflescopes have truly precise and consistent adjustments, so it isn’t uncommon to go back and forth a bit to get it right. That’s perfectly OK, but you have to take your time and make sure the barrel doesn’t get too hot. Once you think you’re there, let the barrel cool completely and then check again. Depending on how many shots were fired, there’s a good chance it’s now time to clean the rifle. There is no set rule, and all barrels are different, but for optimum accuracy it’s probably best to clean the barrel after no more than 20 shots. Now a freshly cleaned barrel will often have a different point of impact than the same barrel after a couple of shots, so I clean at the range, and if that’s my last zero session before taking a rifle hunting, I clean the barrel and then fire a couple of “fouling shots,” thus checking the zero one more time.

002_Make-Your-Decision5. Double-Check, Then Check Again
OK, now the rifle is zeroed perfectly just where you want it. But wait—as they say in the infomercials—there’s more! Do you use a bipod in the field? It’s a great tool, especially in open country, but some rifles will have a different point of impact with an attached bipod than over sandbags. This is the one I’ve noticed, but I suppose the same could be true of just about any field shooting aid. So once you’re all zeroed, fire a couple of shots off your bipod or other shooting aid. You may not be quite as steady, so the results may not be as perfect—but if there’s a significant difference, you should notice it.

Finally, if you’re hunting away from home, make sure you check zero one last time when you arrive in your hunting area. Major temperature and altitude changes will make a difference (“temperature up, bullet strike up; altitude up, bullet strike up”). Other than that I’ve found it fairly rare for a well-mounted scope to come out of zero while traveling, but it can happen, and Murphy’s Law applies. Check your zero before starting your hunt. This is not always easy; I can’t tell you how many times I’ve checked zero in the dark, using car headlights on a target. Whatever it takes, the level of confidence that lies in absolutely knowing your rifle is ready is worth the effort.

  • Bigdog2

    Good Article, though I'd recommend zeroing out the scopes cross hairs before even bore sighting. Also during bore sighting, windage adjustments (left and right) should be made using the scope mounts windage screws rather than using all the scopes internal windage adjustment. Emphasis should also be placed on first shooting at a 25 yard target, before moving the target further away. Most modern calibers in a scoped rifle should print about 1" high at 25 yards to be on or a little high at 100 yards.

    • Bob Tucker

      Bigdog2, If you sight in a rifle like a 308 with a 150 gr bullet, at 25 yards; it will be almost 6 inches high at 100 yards.

      A 243, 80 gr bullet will be almost 7 inches high at 100 yards with a 25 yard zero… look it up.

      • Dave Stark

        I looked it up using Hornady’s ballistic calculator. It’s more like 2.5 inches high for the 150 gr. 308; and 3.0 inches high for the 80 gr. 243. Here is a link:

        • Bob Tucker

          My charts are a little different then. I know from shooting on the range,. Its 6 ” high (technically 5.7″) for the 308 (@ 100 yds) …that’s zeroed in at 25 yds.,,,,,,,,,,,…………….. If you want it on the button for 350 yds , then zero it at 25 yds

      • Randall Crow

        That had to be what happened to me with my 243 last weekend got a Hammer Scope 8-32 from the gun show and mounted it and sighted it quickly before the indoor range closed. in 20 minutes I had the group I wanted dead center at 25 yds ……did not have time to let the barrel cool down and get the last group out. The next day for first day of doe and spike season down here I shot at the doe once at 100 and again at 150 both perfect sight picture….I found the spot where she went through the fence but no sign of any blood or tissue I am pretty sure it was a high gut or maybe lung shot. I need to look at the trajectory profile of 243-100grain with a high mounted scope.

  • Lew

    Zero can actually be achieved with only one round fired (although a second or third shot to confirm is the norm). Here's how: Use a firm and solid sandbag rest. Boresight on the bullseye and align the scope crosshairs to same. Then, from the rest, hold the crosshairs on the bullseye and fire round one. It will hit "on paper" but likely not quite on the bullseye. Then hold the rifle steady on the rest with the crosshairs on the bullseye and without moving the rifle, carefully adjust the crosshairs until they are sighted on the bullet hole made by round one. That's it! Now you have first determined where the rifle hit relative to the crosshairs when it was aimed at the bullseye, and then you adjusted the crosshairs to align exactly where round one hit. To confirm, fire a second round. If you have held everything steady while firing and adjusting the scope, round two will hit on or very nearly on the hole that was made by round one. "A SOLID REST AND A STEADY HOLD" are key, but it works!

    • Calibrator

      Lew nailed it! He is exactly right. This works great and saves ammo!

    • Dave

      I was an instructor for years, and this system works with one correction: Fire a three-shot group first and adjust to the center of group. I've seen experienced shooters fire 5" groups, and adjusting to any one of those shots would have been a mistake. Unless you're a serious competitor, shooting a hundred rounds or more a week, use a group.

    • old vet

      This method works great. But you have to be absolutely sure to hold everything perfectly steady while adjusting things. Also works easier with two, one to look through scope other to move things.

  • gary chenett

    I agee with Big Dog.
    Zero in at 25 yards, why waste your ammo and time to try and zero at 50 yards or more?
    In basic training in the Army and for advanced Infantry training and jungle school training for Vietnam ( 1967/68 The Big Red One 1st/4th Calvary) we zerod in first at 25 yards and then if later you want to take the time to go to 100 yards fine,
    I found that a zero in at 25 yards put me pretty much nuts on at 100 yards always and we were using iron sights no scopes.
    Zeroing at 100 yards wasted allot of time and ammo until you were able to get at least a easy 3" pattern… 25 yards
    Keep 5

    I bought a lead sled and use it with 2 bags of shot pellets for ballast to anchor the Sled downand wow does that ever make a difference

    • Mys_Pa

      Gary, was scrolling comments and saw yours. I served with 1-4CAV in Afghanistan. Thanks for your service!

  • R2STUD

    __ I'm tellin ya pa I heard them squirrls running across the roof again..

    • Lew

      It's all in yer haid, son. All in yer haid. Now go back to sleep . . . ;-)

  • Oedipus

    Lewis nailed it? If Ido as he said and my second shot hits hole one and not the bullseye there is a problem. ( unless you are aiming at hole one with shot two )

  • Pat

    Lew is right on for getting there with one shot. Then the fun starts. Fire a few 3 shot groups to fine tune where you want your zero point to be. Always start with a cold barrel. I like 1-1/2" high @ 100 yds. for most calibers I shoot. This gets me close at 200 and a few inches low at 300 yds. Lead sleds are great for getting zeroed, but your point of impact may change when the gun is shouldered. There is no substitute for shooting a lot of ammo to get good with your rifle. Four to six inch swinging steel plates out to 300 yards make for a fun day of shooting practice

    • Craig

      Why not just use inches, minutes, clicks? If you know your sights were dead on the bull when the shot broke (you are using the "six steps to firing the shot" aren't you) just measure the vertical and horizontal distance the bullet impacted from the bull. Convert the inches into minutes and then make the appropriate adjustments to your sights.
      Say your target is at 25 yards. The bullet strike is one inch high and two inches left. One inch is one MOA at 100 yds. So at 25 yds 1/4" equeals one MOA. Your sights are four minutes high and eight minutes left for this example. If your scope or sight adjustments are one click equeals 1/2 MOA you would adjust eight clicks down and 16 clicks right. Your next shot will be in the bull.

  • Mike Peach

    For recoil management, try the Evo Shield.


    okay so i’m just learning how to use my rifle and i just took it out of its box and confused a little about what the knobs on the top and side are can sombody email me and tell me please thank you.

  • Eddie Pate

    Thanks for writing this in plain and usable terms. It seems there is such a cloud of disinformation on this topic. Every shooter I came across had their own way of zeroing their scope, but this one works and it clicks with me. I improvised a similar way when I began using scopes. .With my vision, a good scope is worth its weight in gold and a properly zeroed one is priceless :) What a lot of people don’t realize is that through the focusing of the scope, you an actually correct for slight vision problems. You can see more clearly through a properly focused scope than if you were standing right there next to your target.

  • Bob Tucker

    With a new scope I shoot 25 yds and adjust to 2 ” under bullseye…. then I shoot 50 yds and adjust, then I do my final adjustments at 100yds…. With the bullet I use its 2″ low at 200 yds…. Its great to look at a chart , but its better to know where the round goes. Each rifle is different.

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