Mounting a scope on a rifle is a fundamental skill for any shooter. Getting it right is critical for accuracy, and learning how to mount a scope on a rifle properly will save you frustration and ammunition. A poorly mounted scope can cause missed shots and a lack of confidence in your gear. This guide will walk you through the process step-by-step, ensuring you have a solid, reliable setup for your next trip to the range or field.
You don’t need to be a master gunsmith to do this job well. With the right tools, a methodical approach, and a bit of patience, you can achieve a professional-level mount at home. Let’s get started by gathering everything you’ll need.
Tools and Materials You’ll Need
Before you begin, make sure you have these items ready. Trying to improvise halfway through can lead to mistakes.
* A quality scope mounting kit (rings and base appropriate for your rifle).
A gunsmithing screwdriver set or hex/Allen keys that exactly fit your screws.
* A torque wrench (inch-pounds, not foot-pounds) is highly recommended.
* Threadlocking compound (like Loctite 242/Blue).
* A bubble level or leveling kit.
* Lens cleaning cloths.
* A stable workbench or vise with protective jaws.
How to Mount a Scope on a Rifle
This is the core process. Follow these steps in order for the best results.
Step 1: Prepare the Rifle and Workspace
Safety first. Ensure the rifle is completely unloaded, with the chamber and magazine empty. Work in a clean, well-lit area. Mount the rifle securely in the vise using non-marring pads, but don’t overtighten. You should have easy access to the top of the receiver.
Step 2: Install the Scope Base
The base bridges the rifle’s receiver and provides a platform for the rings. Clean the receiver threads and the base screw holes with a degreaser. Apply a small drop of blue threadlocker to each screw. This prevents them from vibrating loose over time. Tighten the base screws gradually and evenly in a crisscross pattern, just like lug nuts on a car wheel. If you have a torque wrench, follow the manufacturer’s specification (often 15-30 in-lbs).
Step 3: Lap the Scope Rings (Optional but Recommended)
Ring lapping ensures the rings are perfectly aligned and won’t put stress on the scope tube. It involves using a lapping bar and abrasive compound to gently wear down the high spots inside the rings. This step can greatly improve consistency and is worth the extra time for a precision setup.
Step 4: Set the Eye Relief
This is a crucial step for comfort and safety. Without installing the rings yet, hold the scope on the rifle and assume your normal shooting position. Move the scope forward or back until you see a full, clear picture with no black shadowing around the edges (this is the “eye box”). Mark this position lightly on the scope tube with a pencil. Proper eye relief also ensures you won’t get hit by the scope during recoil.
Step 5: Level the Scope
A canted scope will cause your shots to drift horizontally as range increases. First, level the rifle itself in the vise using a bubble level on a flat part of the receiver or rail. Then, place the scope in the bottom halves of the rings. Use a leveling tool or a plumb line on a distant wall to align the scope’s reticle with true vertical. Double-check everything before proceeding.
Step 6: Install and Torque the Ring Tops
Place the top halves of the rings on. Start all the screws by hand to avoid cross-threading. Using your torque wrench, tighten the screws in a diagonal pattern. A common torque setting for scope ring screws is 15-18 inch-pounds, but always check your ring manufacturer’s instructions. Overtightening is a common mistake that can damage the scope tube.
Step 7: Perform a Final Check
Remove the rifle from the vise. Check all screws one last time with the torque wrench. Look through the scope again to verify eye relief and that the reticle is still level. Give the scope a firm (but not violent) twist with your hands to ensure it doesn’t move. Wipe down the lenses with a clean cloth to remove any fingerprints or dust.
Common Mounting Mistakes to Avoid
Knowing what not to do is just as important.
* Overtightening Screws: This is the number one error. It strips screws, damages scopes, and warps rings.
* Ignoring Eye Relief: Poor eye relief leads to inconsistent shooting and a risk of “scope eye” injury.
* Skipping the Leveling Process: A canted reticle guarantees accuracy problems at longer distances.
* Using the Wrong Tools: Using a regular screwdriver or hex key can strip screw heads. A proper fitting bit is essential.
* Forgetting Threadlocker: Vibration from shooting will eventually loosen screws without it.
Choosing the Right Mounting Hardware
Not all rings and bases are created equal. The type you need depends on your rifle and scope.
* One-Piece vs. Two-Piece Bases: One-piece bases offer more rigidity and are common on modern rifles. Two-piece bases are traditional for some bolt-actions.
* Ring Height: Rings must be tall enough for the objective bell (front lens) to clear the barrel, but as low as possible for a stable cheek weld.
* Ring Type: Standard rings, quick-detach (QD) rings, and cantilever mounts (common on AR-platforms) are the main options. Match them to your intended use.
What to Do After Mounting Your Scope
Your job isn’t quite finished once the scope is physically attached. The next critical step is zeroing the scope, which means adjusting the windage and elevation knobs so the point of aim matches the point of impact at a specific distance. Start at a close range, like 25 yards, to get on paper, then move out to your desired zero distance (e.g., 100 yards). Always use a stable rest and fire three-shot groups, adjusting between each group.
Frequently Asked Questions (FAQ)
How tight should scope rings be?
You should use a torque wrench and follow the manufacturer’s specs. A general range is 15-18 inch-pounds for the ring screws, but some mounts require more or less. Never guess.
Can I mount a scope myself?
Absolutely. With the proper tools and by following detailed instructions like these, most shooters can successfully mount their own scope. It builds familiarity with your equipment and saves money.
Why is my scope moving after I mounted it?
This usually indicates under-tightened screws, a lack of threadlocker, or improperly aligned rings putting uneven pressure on the tube. You should remount it, checking for level and using a torque wrench.
Do I need to lap my scope rings?
For most hunting applications with quality rings, lapping may not be strictly necessary. For long-range precision shooting, it is a highly recommended step to ensure perfect alignment and consistent pressure.
How often should I check the tightness of my scope mounts?
It’s a good habit to check the torque on your mount screws periodically, especially after the first few range sessions or if the rifle has been subjected to rough handling or significant recoil. An annual check is a reasonable maintenance routine.
Mounting a scope correctly is the foundation of accurate shooting. Taking your time during each step, using the right tools, and avoiding common pitfalls will give you a rock-solid platform. Once you’ve confirmed everything is secure and level, you can head to the range with confidence, ready to zero in and enjoy the improved performance a well-mounted scope provides. Remember, a little extra care during setup makes all the difference downrange.