Bore sighting your rifle is a quick and easy method for getting your scope roughly aligned with the barrel before heading to the range. But just how accurate is it? The short answer is: it's not highly accurate, but it's a valuable first step. Bore sighting gets you on paper, saving you time and potentially frustration at the range. However, it shouldn't be considered a substitute for proper zeroing.
Understanding Bore Sighting
Bore sighting involves aligning the scope's crosshairs with the barrel's bore using a bore sighting tool. These tools are typically inserted into the barrel's muzzle or breach and allow you to see the line of sight through the scope. This aligns the scope with the general trajectory of the bullet.
Limitations of Bore Sighting
While bore sighting gets you in the ballpark, several factors limit its accuracy:
1. Scope Mounting Inconsistency:
Even with careful mounting, slight misalignments can occur. If your scope rings aren't perfectly level, or if the scope isn't perfectly centered in the rings, this introduces error.
2. Barrel Variation:
The bore isn't perfectly straight in all rifles. Slight variations in the barrel's rifling or manufacturing can subtly alter bullet trajectory, causing differences between the bore sight and actual bullet path.
3. Ammunition Variations:
Different types of ammunition can have slightly different ballistic properties. The bore sight alignment, assuming a specific type of ammunition, may not be perfectly accurate when using different cartridges.
4. Environmental Factors:
While less significant at short ranges, environmental factors such as wind and temperature can affect bullet trajectory and can throw off the bore sighting's effectiveness.
Accuracy Expectations
Expect bore sighting to get your shots on the target at reasonable ranges (e.g., 25 yards). You shouldn't expect pinpoint accuracy. Consider it a method for getting the first shots within the target's circumference; you'll still need to adjust the scope's elevation and windage through proper zeroing at the range. Think of it as a starting point, not a final solution.
When is Bore Sighting Useful?
Bore sighting proves most valuable in these situations:
- New Scope Installation: It's far easier to adjust a scope from a position close to the target than to repeatedly fire rounds while adjusting hundreds of yards away from it.
- Scope Replacement: Similar to new scope installation, getting a rough zero quickly is ideal here.
- Quick Sight Alignment: In situations where time is limited or resources are scarce, a quick initial alignment is helpful.
The Importance of Proper Zeroing
Remember, bore sighting is not a substitute for proper zeroing. After bore sighting, you must go to the range and fine-tune your scope's adjustments for optimal accuracy using a systematic zeroing process. This process involves firing several shots at various distances and making incremental adjustments based on the shot group's location.
Conclusion
Bore sighting provides a reasonable starting point for scope alignment. It saves time and frustration by ensuring your first shots land on the target, not miles off. However, it's crucial to understand its limitations and to always follow up with proper zeroing at the range to achieve optimal accuracy. Don't rely solely on bore sighting for precision shooting.
