You’ve made a significant investment in a quality rifle and a precision optic. But all that potential for accuracy can be completely undone by a simple, yet critical, mistake during installation. A scope that isn’t mounted correctly will never hold zero, will frustrate you at the range, and could cost you a successful hunt. The good news is that with the right tools and a methodical approach, this is a task you can confidently tackle yourself.
Learning how to mount a scope correctly is a fundamental skill for any shooter. It’s the physical link between your eye and your rifle, and getting it right ensures consistency, reliability, and, most importantly, safety. This guide will walk you through the entire process, from gathering your tools to the final torque checks, so you can head to the range with confidence.
Gathering Your Essential Tools
Before you even think about touching your scope, you need the right tools for the job. Using improper tools is the fastest way to damage your expensive equipment. You will need a set of gunsmithing screwdrivers or bits that exactly fit the base and ring screws. Using a standard Phillips head that “sort of fits” will strip the screw head. A torque wrench, preferably an inch-pound model, is non-negotiable for applying the correct amount of force. You’ll also need a stable workbench, a gun vise (or a set of padded clamps), and the correct mounting hardware for your specific firearm. Don’t forget a leveling kit or a set of feeler gauges; this small detail makes a huge difference.
Selecting the Right Mounts and Rings
Not all scope mounts are created equal. The first step is choosing a solid base. This could be a one-piece base or a two-piece set, depending on your rifle’s action. Next, you need to select the rings. The ring height is crucial—it must be tall enough to ensure the objective bell of the scope clears the barrel but low enough to allow for a comfortable, consistent cheek weld. The ring diameter must also match the tube size of your scope (typically 1 inch or 30mm). Investing in quality, matched rings and bases from a reputable manufacturer is one of the best decisions you can make for long-term performance.
The Step-by-Step Guide on How To Mount a Scope Correctly
Now for the main event. Let’s break it down into a clear, manageable process.
Step 1: Prepare the Firearm and Mount the Base. Ensure the rifle is unloaded and the action is open. Clean all the screw holes in the receiver and the base with a degreaser. Apply a small drop of blue (removable) thread-locker to the base screws. Screw the base onto the receiver, but only hand-tight for now.
Step 2: Install the Bottom Rings and Set the Scope. Attach the bottom halves of the rings to the base, again hand-tight. Carefully place the scope into the bottom rings. Before you even put the top rings on, this is the time to set your eye relief. Slide the scope forward or backward until you have a full, clear field of view with no shadowing when you shoulder the rifle naturally. Your eye should be safe from the scope’s eyepiece during recoil.
Step 3: The Critical Leveling Process. This is where many people go wrong. You need to ensure the scope’s reticle is perfectly level with the world. Place a small level on a flat part of the rifle’s action (not the barrel). Then, while supporting the scope, gently rotate it until the crosshairs appear level. You can use a leveling tool that sits in the scope’s elevation turret or stack feeler gauges on either side of the scope tube to prevent it from rotating. Take your time with this step.
Step 4: Secure the Top Rings and Final Torque. Once everything is level, place the top rings on and start threading the screws by hand. Now, using your torque wrench, follow a star pattern (like tightening a car tire) to slowly bring the screws down to the manufacturer’s specification. This is typically between 15-25 inch-pounds for the ring screws, but always check your specific ring’s manual. Do the same for the base screws. Over-tightening can crush the scope tube or strip the threads.
Avoiding Common Mounting Mistakes
Even with a good guide, it’s easy to make a few key errors. The most common is over-tightening, which we’ve already addressed. Another is improper eye relief, leading to “scope bite”—a nasty cut on your eyebrow from recoil. Rushing the leveling process will cause canting, meaning your shots will drift horizontally as you adjust for distance. Finally, using cheap, mismatched rings is a recipe for failure. They may not hold alignment, putting stress on the scope tube and causing zero to shift.
Final Checks and Heading to the Range
With the scope mounted, do a physical check. Ensure it doesn’t move in the rings and that all screws are secure. Now it’s time to boresight. You can use a laser boresighter or simply remove the bolt and look down the bore to roughly align the scope with a distant object. This gets you on paper at the range. From there, it’s a matter of firing groups and making careful adjustments to zero your rifle for your chosen ammunition.
Taking the time to mount your scope properly is one of the most rewarding tasks in shooting sports. It builds a deeper connection with your equipment and provides the solid foundation needed for precision. By following these steps—using the right tools, carefully leveling the scope, and applying the correct torque—you transform your rifle and optic into a single, reliable system you can trust in any situation.