Boresighting is a crucial step in zeroing a rifle scope, ensuring that the crosshairs of the scope are aligned with the rifle's bore before taking it to the range for live fire. This can save time and ammunition by ensuring that the scope is roughly aligned with the barrel’s trajectory. There are several methods for boresighting, each with its advantages and disadvantages.
Laser Boresighting Method
The laser boresighting method is a quick and effective way to align your rifle scope. It involves using a laser device that simulates the trajectory of a bullet, allowing you to easily align the scope reticle with the point of impact.
Steps:
1. Ensure Rifle is Unloaded and Secure:
- Double-check that the rifle is unloaded. Remove any live rounds from the chamber and magazine to ensure safety.
- Secure the rifle in a stable, controlled environment to prevent any accidental movements during the boresighting process.
2. Insert Laser Boresight into Chamber:
- Insert the laser boresight tool into the rifle's chamber. Ensure that the tool is compatible with your rifle's chamber size.
3. Mount Rifle Securely and Power on Laser:
- Place the rifle on a stable rest or bench. Make sure the rifle is securely held in place to minimize any movement.
- Turn on the laser device, which will project a laser dot downrange, simulating the bullet's path.
4. Align Scope Reticle with Laser Dot:
- Look through the rifle’s scope and adjust the windage (left or right) and elevation (up or down) to align the reticle with the laser dot projected on the target.
- This process will give you a rough alignment between the scope and the bore.
5. Make Necessary Windage and Elevation Adjustments:
- Use the windage and elevation knobs to fine-tune the scope's reticle until it matches the laser dot exactly.
- You should adjust both horizontally and vertically to ensure the scope's crosshairs match the laser's projected point of impact.
6. Confirm Alignment at Multiple Distances:
- After making adjustments, confirm that the alignment holds at different distances by checking the position of the laser dot in the scope at different ranges.
- You can use a second target at a longer distance to ensure accuracy over longer ranges.
Traditional Boresighting Method
Traditional boresighting is a more hands-on method that requires looking through the rifle’s bore to align the scope's reticle. While it's more time-consuming than laser boresighting, it’s still an effective and reliable technique.
Steps:
1. Remove the Bolt (If Possible)
- If your rifle allows, remove the bolt to gain a clear view down the barrel. This will help you see the target directly through the bore.
- If your rifle doesn’t allow bolt removal, ensure the rifle is still stable and secure for this process.
2. Secure the Rifle in a Stable Position
- Place the rifle on a rest, sandbags, or a secure platform to prevent movement during the process.
- Ensure the rifle is positioned so that you can look straight through the bore toward the target.
3. Look Through the Bore at the Target Center
- Look down the barrel of the rifle. The target should be centered within the bore, and you should aim to align the bore with the point where you want to strike (usually the center of the target).
- Keep your eye steady and maintain focus on the target through the bore.
4. Adjust the Scope to Align with the Bore's Point of Aim
- Without moving the rifle, adjust the scope’s reticle to match the center of the target as seen through the bore.
- This might require small adjustments to both windage and elevation knobs to bring the reticle to the same point of aim as the barrel.
5. Verify Alignment at Multiple Ranges
- After the initial boresighting, it's important to verify the alignment at various distances (usually 25 yards and 100 yards or more).
- This helps ensure that the scope is aligned with the barrel across different ranges and prevents significant errors in windage or elevation at longer distances.
Final Steps
Once you've completed the boresighting process using either the laser or traditional method, it’s important to finalize everything and confirm the alignment is solid before heading to the shooting range for live fire testing.
Steps
1. Confirm All Adjustments are Locked
- Double-check that all windage and elevation adjustments have been properly locked in place. Many scopes have lockable turrets or screws to prevent accidental adjustments during transport or use.
- Ensure that the focus, parallax, and magnification settings are also correctly adjusted to your preferences.
2. Record Initial Settings
- If your scope has adjustable turrets or dials, record the initial settings (such as zero points for windage, elevation, and any custom settings you may have applie.
Tips for Success in Scope Mounting and Alignment
1. Use Quality Mounting Hardware
Selecting high-quality mounting hardware is essential for a secure and stable optic setup. Cheap or poorly made mounts and rings can introduce flex, misalignment, or looseness that could affect your accuracy. Invest in solid, durable hardware to ensure the scope remains firmly in place during shooting.
2. Follow Manufacturer Torque Specifications
Each scope mount and ring set typically comes with specific torque recommendations. It’s crucial to follow these torque settings precisely to avoid over-tightening or under-tightening, both of which can lead to damage or instability. Use a calibrated torque wrench to ensure consistent and proper torque.
3. Verify Levels on Multiple Axes
Before securing your scope completely, make sure it’s level both horizontally and vertically. A canted or improperly aligned scope can affect your accuracy. Use a spirit level or specialized scope leveling tool to verify the alignment on both the rifle and the scope itself.
4. Start Boresighting at Shorter Distances
When you begin the boresighting process, start at a shorter distance (typically around 25 yards). This will allow you to get the scope roughly aligned with the bore of the rifle before fine-tuning it at longer ranges. Shorter distances make it easier to correct large discrepancies.
5. Document All Adjustments
Keep track of all your adjustments throughout the process—especially windage and elevation. This will help you understand how much correction is required for a perfect sight picture and can be a valuable reference for future sight-in sessions or troubleshooting.
6. Use Consistent Eye Position
Maintaining a consistent eye position while using the scope is critical to ensuring the reticle remains aligned with your line of sight. Variations in your eye placement can cause the point of impact to shift or introduce parallax error.
7. Maintain Proper Cheek Weld
A proper cheek weld ensures your face remains in the same position every time you shoulder the rifle, which in turn helps with consistency in sight alignment and eye relief. Establishing a natural, comfortable cheek weld will allow for faster target acquisition and more accurate shots.
Common Mistakes to Avoid in Scope Mounting and Alignment
1. Over-tightening Mount Screws
Over-tightening the screws can warp the scope tube or mount, leading to misalignment or stress on the optic. It can also cause the rings to grip the scope too tightly, potentially damaging the lenses. Always use the recommended torque settings and avoid over-tightening.
2. Improper Ring Alignment
Poorly aligned rings can create uneven pressure on the scope tube, resulting in distortion or scope failure. Make sure the rings are properly aligned with each other and the scope, and use ring lapping tools if necessary to ensure the best fit and alignment.
3. Incorrect Eye Relief
Improper eye relief can lead to a range of issues, including an inability to obtain a full field of view, a blurry image, or worse—scope “eye relief” injuries (especially with high-recoil rifles). Be sure to adjust your scope so that the eye relief matches the manufacturer’s specifications and provides a comfortable sight picture.
4. Uneven Ring Tension
Uneven tightening of the rings can lead to a misaligned scope, potentially causing accuracy problems. Tighten the screws incrementally, alternating between the rings to ensure even pressure is applied around the entire scope. This also helps prevent distortion.
5. Neglecting to Level the Scope
Failing to properly level the scope can introduce crosswind errors or parallax issues that significantly affect your shooting accuracy. Always check both the rifle’s receiver and the scope to make sure they are perfectly level. A slight misalignment can be magnified at longer distances.
6. Using the Wrong Size Rings
Using rings that are too small or too large for your scope can cause improper mounting, leading to poor alignment, scope damage, or failure. Verify the correct ring size based on the scope’s diameter and your rifle’s rail type (Picatinny, Weaver, etc.) before mounting.
7. Skipping the Boresighting Process
Skipping the boresighting process is a common mistake that can waste time at the range and hinder accuracy. Boresighting ensures your scope is roughly aligned with the bore, so you don’t have to waste shots trying to adjust the scope at longer distances. Always perform a basic boresight before heading to the range for zeroing.
By following these tips and avoiding common mistakes, you can ensure that your scope is securely mounted and correctly aligned, leading to improved accuracy and more consistent performance when shooting and hunting.
