Last November, I was guiding a client through the Bob Marshall Wilderness when his rifle took a nasty spill off a ledge. The scope survived, but it was knocked completely out of zero. With a massive bull elk spotted just two valleys over and no gunsmith for a hundred miles, we had exactly one evening to remount and dial in that scope using nothing but basic tools and hard-earned knowledge. That hunt ended successfully because understanding scope adjustment isn’t just convenient—it’s essential.
After twenty-five years of mounting scopes on everything from military M24s to beat-up ranch rifles, I’ve learned that even the finest glass money can buy becomes expensive junk if you don’t know how to properly mount and adjust it. Whether you’re preparing for your first hunt or troubleshooting problems with your current setup, this guide will walk you through every critical adjustment your scope needs.
The Foundation: Proper Scope Mounting
My grandfather used to say, “A house built on sand won’t survive the first storm.” The same principle applies to mounting your scope. Get this wrong, and you’ll be chasing your zero all season long. Trust me, I learned this lesson the hard way during a week-long backcountry hunt in Alaska where my hastily mounted scope gradually worked loose, turning what should have been easy shots into frustrating misses.
There are three critical elements to get right when mounting your scope: height positioning, forward and rear placement, and making sure everything sits level. While plenty of folks pay a gunsmith to handle this task, you can absolutely master it yourself with patience and attention to detail.
Setting Your Scope Height: Finding the Natural Eye Box
The relationship between your cheek weld and scope height determines whether you’ll shoot comfortably for hours or develop a sore neck after twenty rounds. Here in Montana, where a single elk hunt might involve dozens of shots between sighting in, practice, and the actual harvest, comfort matters as much as accuracy.
Start by assuming your natural shooting position with the rifle unloaded and pointed in a safe direction. Rest your full cheek weight on the stock and close your eyes. Get comfortable—this should feel as natural as shouldering the rifle to check on a distant coyote threatening the chicken coop. Now open your eyes.
Can you see clearly through the scope without lifting or pressing your head? If you’re craning your neck up or mashing your face down into the stock, you need different height rings. I keep a selection of ring heights in my workshop because every rifle and shooter combination requires something different.
When Sarah, my wife, started hunting with me fifteen years ago, we discovered her shorter face structure meant she needed higher rings than what worked for me on the same rifle. If you’re constantly switching between shooters or prefer flexibility, consider quality quick-detach mounts that maintain zero when removed and replaced.
For rifles with adjustable combs or those accepting add-on cheek risers, you’ve got another option. I’ve used everything from foam pipe insulation secured with athletic tape (my military field expedient method) to proper adjustable risers. The goal remains the same: your eye should naturally align with the scope when your cheek touches the stock.
Here’s something that took me years to fully appreciate: mounting your scope as low as practical to the bore helps with accuracy. The closer your line of sight sits to the bullet’s path, the less variance you’ll experience from canting errors or point-of-aim shifts at different distances. But don’t go so low that you’re looking through the top edge of your vision or your eyeglasses start distorting the image.
One specific challenge I see frequently here at my training courses involves AR-platform rifles with fixed front sights. Rather than mounting your scope unnecessarily high to clear that front post, which creates its own problems, consider removing or replacing the gas block. The improved sight picture and lower scope position will pay dividends in accuracy.
Establishing Proper Eye Relief: Avoiding Scope Bite
During my Ranger days, we called it “getting kissed by the scope”—that semicircle cut above the eyebrow that marks someone who learned about eye relief the hard way. I’ve patched up more scope cuts than I care to remember, usually on powerful rifles where excited hunters forgot their fundamentals in the heat of the moment.
Eye relief represents the distance between your eye and the rear lens of the scope. Too close, and recoil drives that metal edge into your forehead. Too far, and you lose field of view or can’t see the full sight picture. Getting it right means finding that sweet spot where you see a complete, clear image without any black ring around the edges—what we call scope shadow.
Mount your scope rings loosely on the rail, just tight enough to hold the scope but loose enough to slide it forward and backward. Place your rifle on a solid rest—I use sandbags on my workshop bench, but a backpack works fine in the field. Assume your natural shooting position again.
Slide the scope slowly backward until you notice a black ring creeping in from the edges of your view. Mark that spot mentally, then push it forward until the shadow disappears completely. You want to position your scope at the forward edge of this clear viewing zone, giving yourself maximum protection from recoil while maintaining a full sight picture.
For heavy-recoiling rifles—anything from .300 Winchester Magnum up through the big bore dangerous game calibers—I recommend at least four inches of eye relief. My .338 Lapua, which I use for long-range elk hunting, has nearly five inches of relief. Yes, it required a cantilever mount to achieve proper positioning, but I’ve never had to explain a scope cut to anyone.
Speaking of cantilever mounts, they’re invaluable when you need to position a scope further forward than standard rings allow. This often happens with rifles that have short rails or when mounting longer scopes. I’ve used them successfully on everything from scout rifles to precision bolt guns where standard ring placement just wouldn’t work.
Getting Everything Level: The Foundation of Accuracy
Three winters ago, I spent two hours helping a frustrated hunter who couldn’t understand why his carefully zeroed rifle shot progressively further left as distance increased. The problem? His scope sat cocked about five degrees to the right. Every elevation adjustment he made also pushed his windage off because the adjustments weren’t tracking truly vertical and horizontal.
A canted scope creates diagonal adjustments—turn the elevation turret and you’re also affecting windage. Dial in windage corrections and you’re inadvertently changing elevation. For scopes with ballistic reticles, ranging marks, or holdover points, none of those features work correctly unless your scope sits perfectly level.
I’ve tried every leveling method from plumb bobs to smartphone apps, but nothing beats a quality scope leveling kit. The setup I’ve used for the past decade employs precision bubble levels that attach to both your rifle’s action and the scope itself. You level the rifle first, then adjust the scope until both bubbles center up.
In a pinch, you can use the old carpenter’s trick: hang a weighted string (plumb line) at 100 yards and align your vertical crosshair with it while the rifle sits solidly bagged. It works, but takes patience and a windless day—something we don’t see much of here in Montana.
Remember to check your level after tightening the rings. I’ve seen scopes rotate slightly during the tightening process, especially with cheaper rings. Tighten gradually in a cross-pattern, like lug nuts on a wheel, checking level after each sequence.
Achieving Crystal Clear Vision: Eyepiece Focus
One autumn morning, guiding a hunter from back East, I watched him struggle with what he thought was a defective scope. “Either the target’s fuzzy or the crosshairs are,” he complained. The scope was fine—he’d just never learned to properly focus the eyepiece. This single adjustment can mean the difference between eye strain after an hour of glassing and comfortable all-day observation.
Unlike focusing on your target (which happens with parallax adjustment), the eyepiece focus adjusts the reticle to match your individual eyesight. Everyone’s eyes are different, which is why this adjustment is crucial and personal to each shooter.
Point your scope at a blank surface—the sky works well, or a white wall if you’re indoors. Turn the eyepiece bell (the adjustment ring closest to your eye) all the way to one extreme. The reticle will appear blurry, which is exactly what we want to start.
Now, while looking through the scope, slowly turn the eyepiece the opposite direction. Watch that reticle carefully. It will gradually sharpen, reach perfect clarity, then start to blur again if you go too far. Work back and forth with increasingly fine adjustments until you find the exact point where the reticle appears sharpest.
Here’s a critical tip I share with every student: look away from the scope for a few seconds between adjustments. Your eye will try to compensate for poor focus, which can fool you into accepting a less-than-perfect setting. Fresh looks give you honest feedback.
Some modern scopes feature fast-focus eyepieces that make this process quicker, but the principle remains identical. Once set correctly for your eye, you typically won’t need to adjust this again unless someone else uses your rifle or your vision changes significantly.
The Heart of Accuracy: Windage and Elevation Adjustments
During my years instructing at various training facilities, I’ve seen experienced hunters who still didn’t fully understand how their scope adjustments actually work. They’d spin turrets hopefully, fire a group, then spin some more, eventually getting close through trial and error rather than understanding.
Your scope’s internal adjustment system works like a precise aiming device that moves your point of aim to match your point of impact. When you turn those turrets, you’re actually moving the entire reticle within the scope tube. Understanding this relationship transforms zeroing from guesswork into a systematic process.
Mastering Elevation Adjustments
The elevation turret—that’s the one on top of your scope—controls vertical bullet impact. After thousands of rounds downrange and years of teaching, I’ve developed a simple mental model: think of the turret as a precision screw that raises or lowers your point of impact.
During a military qualification, I learned this lesson under pressure. My rifle was shooting six inches low at 100 meters with seconds to get it corrected. Understanding that my scope adjusted in quarter-MOA clicks, I knew exactly how many clicks I needed: twenty-four upward clicks to raise my impact those six inches. No guessing, no wasted ammunition—just mechanical precision.
Most scopes today adjust in either quarter-MOA (about quarter-inch at 100 yards) or tenth-MIL increments. MOA scopes remain most common in America, while military and competitive shooters often prefer MILs. I’ve used both extensively and can work with either, though I default to MOA for hunting applications because it translates easily to inches at common hunting distances.
When your bullets impact low, you need to raise your point of impact by turning the elevation turret in the “up” direction—usually counterclockwise when viewing from above. Think about unscrewing that turret to raise it. Hitting high? Turn it clockwise (down) to lower your impact point.
Here’s a field technique that’s saved me countless rounds: after firing a solid three-shot group, calculate exactly how many clicks you need rather than making small adjustments and checking. If you’re four inches low at 100 yards with quarter-MOA adjustments, that’s sixteen clicks up. Make the adjustment confidently and verify with another group.
Fine-Tuning Windage Corrections
That side turret controls horizontal adjustments, moving your bullet impact left or right. In the Montana mountains where I guide, wind becomes a constant companion, sometimes shifting direction three times during a single shooting session. Understanding windage adjustment isn’t optional—it’s survival for your success rate.
The mechanics mirror elevation: turn the windage turret right (marked “R” on most scopes) to move bullet impact right, left (marked “L”) to move impact left. Each click represents the same angular measurement as your elevation turret, maintaining consistency across adjustments.
However, I rarely adjust windage for temporary wind conditions during a hunt. Instead, I’ll hold off using the reticle’s reference points or simply aim into the wind. Save windage turret adjustments for zeroing and persistent winds that won’t change. There’s nothing worse than dialing in six minutes of right wind, having conditions change, then forgetting to dial back to zero for your next shot.
Scout, my German Shorthaired Pointer, has actually become my wind indicator over the years. When his ears start flapping consistently in one direction, I know we’re dealing with enough wind to matter. Under 10 mph, most hunting cartridges don’t need correction inside 300 yards. Beyond that, or in stronger winds, understanding your bullet’s behavior becomes critical.
For those using smartphone ballistic apps—and I recommend them for serious long-range work—remember that wind values need constant updating. The wind at your shooting position often differs dramatically from conditions at the target. I’ve seen bullets pushed two feet sideways at 400 yards by crosswinds that felt mild where I stood.
Advanced Adjustments: Parallax and Magnification
Beyond basic zeroing, modern scopes offer refinements that can significantly improve your accuracy. Understanding when and how to use these adjustments separates competent shooters from truly skilled marksmen.
Eliminating Parallax Error
Parallax might sound like complicated physics, but the concept is straightforward: when your target image and reticle don’t appear on the same focal plane, the crosshairs seem to move on the target as you shift your eye position. This creates accuracy problems that no amount of careful shooting technique can overcome.
I discovered parallax the hard way during a prairie dog hunt in eastern Montana. Despite perfect conditions and solid shooting positions, my impacts wandered unpredictably. An old-timer watching me shoot noticed my head position varied slightly between shots. “Your parallax is off,” he said, then taught me a lesson I’ve never forgotten.
Scopes without parallax adjustment are factory-set for a specific distance—usually 100 or 150 yards for hunting scopes. Within reasonable ranges of that distance, parallax won’t significantly affect accuracy. But stretch the distance or shoot extremely close, and parallax error creeps in.
Adjustable parallax comes in two forms: side focus (a knob on the left side of the turret housing) or adjustable objective (a ring around the front lens). Both accomplish the same goal using different mechanical approaches. My long-range rifles all feature side focus for convenience, while some of my rimfire scopes use adjustable objectives.
To properly set parallax, get stable behind your rifle with the crosshairs on target. Move your head slightly up and down, left and right, while watching the reticle. If it appears to float or move relative to the target, adjust the parallax until the reticle stays locked on one spot regardless of small head movements.
Don’t trust the marked distances on parallax adjustments—they’re estimates at best. Your eyes might focus differently, atmospheric conditions affect light transmission, and manufacturing tolerances vary. Always verify parallax-free status by the head movement test, not by matching numbers to actual distance.
Optimizing Magnification Power
Variable magnification expanded the versatility of riflescopes tremendously, but knowing when and how to adjust power separates average shooters from experts. That magnification ring seems simple enough—turn it to zoom in or out—but proper use requires understanding the tradeoffs.
Higher magnification doesn’t automatically mean better accuracy. During my sniper training, instructors hammered home a counterintuitive truth: excessive magnification often hurts more than helps. You magnify every tiny movement, reduce field of view, darken the image, and potentially increase mirage effect.
For most hunting situations inside 300 yards, I keep magnification between 4x and 9x. This provides adequate target resolution while maintaining enough field of view to track moving game and find targets quickly. Only for true long-range shots—400 yards and beyond—do I dial up toward maximum power.
Lower magnification shines in timber hunting where shots come fast at close range. Scout and River have jumped plenty of whitetails from thick cover where 3x or 4x magnification meant the difference between filling the freezer and watching a white flag disappear.
Remember that changing magnification on second focal plane scopes affects your holdover points and ranging capabilities if your reticle includes those features. First focal plane scopes maintain consistent subtensions throughout the magnification range, though the reticle appears to grow and shrink. Choose based on your primary use—I prefer second focal plane for general hunting, first focal plane for dedicated long-range rifles.
Field Zeros and Environmental Considerations
Theory and bench shooting only take you so far. Real competence comes from understanding how environmental factors affect your zero and knowing when adjustments are necessary versus when to hold steady and trust your setup.
Temperature swings affect zero, especially with certain powders and barrel profiles. My lightweight mountain rifle shoots nearly two inches different at 100 yards between a 20-degree November morning and a 90-degree August afternoon. I maintain a data book with zeros for different conditions, learned through meticulous range work across all four Montana seasons.
Altitude changes matter more than many hunters realize. A rifle zeroed at sea level shoots significantly different at 8,000 feet. The thinner air creates less drag, allowing bullets to maintain velocity longer and drop less. When guiding hunters from low elevation states, I always insist on checking zero after arriving in Montana’s high country.
Ammunition changes require re-zeroing, even when using the same bullet weight. Different manufacturers use varying powders, primers, and loading specifications. I’ve seen identical bullet weights from different makers impact six inches apart at 100 yards. This is why I buy hunting ammunition in bulk lots—maintaining consistency across multiple seasons.
Practical Zeroing Process: From Bore Sight to Confirmed Zero
Let me walk you through my actual zeroing process, refined over countless rifles and thousands of rounds. This method saves ammunition, time, and frustration while delivering consistent results.
First, I bore sight using either a laser bore sighter or the traditional method of looking through the bore at 25 yards. This gets you on paper without wasting ammunition. For bolt actions, remove the bolt and look down the bore at a target, then adjust the scope to match without moving the rifle.
Start at 25 yards regardless of your intended final zero distance. Fire one careful shot from a solid rest. The close range eliminates most environmental variables and ensures you’re on paper. Adjust to center that impact at 25 yards.
Move to 100 yards and fire a three-shot group, allowing the barrel to cool between shots. Never zero with a hot barrel unless you plan to hunt with one—which you shouldn’t. Calculate the center of your group and adjust accordingly. Fire another three-shot group to confirm.
For most hunting applications, I prefer a 200-yard zero. This puts me about 1.5 inches high at 100 yards and allows point-blank shooting out to 250 yards on deer-sized game. Mountain hunters might prefer a 300-yard zero for longer average shots, while timber hunters could stick with 100 yards.
Always confirm your zero with the exact ammunition you’ll hunt with, from field positions you’ll actually use. That perfect bench zero might shift when shooting from sticks, off a backpack, or from other field positions.
Troubleshooting Common Problems
Over years of helping frustrated shooters diagnose scope problems, I’ve cataloged the most common issues and their solutions. Understanding these saves time, money, and potentially that once-in-a-lifetime shot opportunity.
When groups suddenly open up or shift, check ring and base tightness first. I’ve traced more accuracy problems to loose mounting hardware than actual scope failures. Use proper torque specifications and quality thread locker on all mounting screws.
If you can’t achieve zero within your adjustment range, suspect misaligned rings or bases. Burris Signature rings with polymer inserts allow correction without stressing the scope tube. For serious misalignment, consider having a competent gunsmith bed your bases or true your receiver.
Wandering zero often indicates internal scope problems—broken reticle, failed erector system, or loose internal lenses. The “tall target test” diagnoses tracking issues: fire a group, dial up 20 MOA, fire another group, and measure. The distance should match your scope’s specifications exactly.
When parallax adjustment doesn’t eliminate reticle movement, check for consistent cheek weld. Inconsistent head position creates the same symptoms as parallax error. Adding a raised cheek piece or adjustable comb often solves persistent “parallax” problems that aren’t actually parallax-related.
Maintenance and Long-Term Care
Your scope represents a significant investment that should last decades with proper care. My oldest scope, a Leupold that’s traveled from Afghanistan to Alaska, still tracks perfectly after twenty years because I maintain it religiously.
Clean lenses only when necessary using proper lens cloths and cleaning solutions. Rubbing dirt across lens coatings with your shirt destroys more scopes than impacts do. I carry lens pens and microfiber cloths specifically designed for coated optics.
Protect turrets and lenses during transport and storage. Quality scope covers prevent 90% of field damage. Those rubber bikini covers might not look tactical, but they’ve saved countless scopes from Montana’s sideways rain and blowing snow.
Check and maintain proper torque on all mounting hardware annually. Temperature cycles and recoil gradually loosen screws. Mark witness lines on rings and bases with a paint pen to quickly identify any movement.
Store rifles muzzle-up or horizontally to prevent oil migration into the scope. I’ve seen more than one scope’s internals contaminated by excessive gun oil creeping up from the action during improper storage.
The Mental Game: Building Confidence Through Understanding
Technical knowledge means nothing without confidence in your equipment. Understanding exactly how your scope works, why adjustments affect impact, and what each component does builds the trust necessary for precise shooting under pressure.
Practice adjusting your scope regularly, even during the off-season. Dial elevation for different distances, return to zero, and verify repeatability. The mechanical confidence from knowing your scope returns exactly to zero after adjustments cannot be overstated.
Keep a data book recording zeros, ammunition lots, environmental conditions, and any adjustments made. This historical record becomes invaluable for diagnosing problems and maintaining consistency across seasons.
Remember that perfect equipment doesn’t make a marksman—but understanding your equipment thoroughly removes one variable from the shooting equation. When that trophy buck steps out at last light, or when meat for the winter depends on your next shot, confidence in your scope’s adjustments lets you focus on the fundamentals that matter.
Closing Thoughts: Your Scope as a Lifetime Tool
After all these years guiding hunters and teaching marksmanship, I’ve learned that scopes are like any other tool—they’re only as good as the knowledge behind them. That high-dollar scope collecting dust in your safe won’t make you a better shooter, but understanding how to properly mount, adjust, and maintain even a modest scope will dramatically improve your field performance.
Take time to truly learn your equipment. Set up targets at your range and practice adjusting turrets. Get comfortable with the mechanical relationship between adjustments and impact. Build muscle memory for your scope’s controls so adjustments become automatic under stress.
Most importantly, verify everything in field conditions. That perfect indoor zero might shift when you’re breathing hard at 9,000 feet with frozen fingers and a racing heart. The wilderness doesn’t care about your bench groups—it demands practical competence earned through deliberate practice.
Your scope should become an extension of your shooting system, as familiar as your trigger pull and as trusted as your favorite hunting boots. Achieve that level of integration, and you’ll find consistent accuracy comes naturally, whether you’re punching paper at the range or filling tags in the backcountry.
Remember: practice makes permanent, so practice it right. Every adjustment you make, every zero you confirm, and every bit of knowledge you gain about your scope makes you a more complete marksman. The confidence that comes from truly understanding your equipment will serve you well when the moment of truth arrives.
Stay safe out there, respect the game, respect the land, and always remember—your best survival tool is the six inches between your ears, but a properly adjusted scope sure helps when dinner depends on your next shot.