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How to Tell If a Scope is Bad and When to Fix It

How to Tell If a Scope is Bad

When I was a newbie to shooting, I made the big mistake of not checking my scope for damages or wear and tear.

I never knew I was shooting with a damaged scope!

Here is a quick list of how to tell if your scope is terrible and when to repair it. It answers how to handle dust build-up and when to replace an old scope.

There are advantages for a newbie, double for those who hunt or are in the field from a distance.

Here is a short guide on scope quality and repair.

10 Signs and Causes That Your Scope is Bad

Rifle and bullet casings on table

How to tell if a scope is bad is a skill that only comes with practical experience and technical knowledge.

I learned the hard way that scope problems can be unpredictable and problematic in the middle of shooting performance, causal or otherwise.

Even worse, hard to diagnose.

However, I will show you a list of the most common red flags to look out for.

On account of any of these signs, a participant in firearms may see how their performance does correspond with missing their mark.

1. Noticeable Point of Impact Deviation with Every Shot

Poor accuracy was a HUGE telltale sign for me, no matter how much I zeroed in or adjusted my turrets.

Accurate shooting may be more of a hallmark of a skilled shooter with accounting for elevation, wind, and recoil.

However, there can be instances that it’s genuinely FAULTY equipment!

In my experience, I could let a few shots go if it was just slightly off target, but margins that are TOO WIDE are red flags.

2. Horizontal or Vertical Uneven Tracking

When tracking your point of impact, they reveal that each shot doesn’t form a straight line, vertically or horizontally.

This, again, can be an issue of the shooter, but it can also be an equipment issue.

A good test that I learned was to compare shots with another rifle that is verified to be working. Install the scope on another rifle and test it out.

If there is a noticeable discrepancy, there are probably scope problems.

3. Point of Impact is Not in Sync with Input Clicks

The accuracy of your rifle can hinge on how calibrated your adjustment dials are.

However, accurately shooting is thrown out the window when malfunctions occur.

So if you still miss your target despite your adjustment dials being set, there is an issue with your rifle scope.

4. Unpredictable Errors in Click Values

Usually, I can tell the necessary number of click values for an adjustment when I use a rifle scope.

Being off by 1 or 2 clicks is understandable, but too large of a disparity means problems.

It shows how advantageous it is to hear those needed click values!

5. Failure to Zero After Several Shots

It is possible to accurately zero your target after only 2 shots. It takes most people several shots, but it’s the margin.

However, even after such an adjustment, you may need to consider finding a new scope if you can still not hit your target at the center.

REMEMBER: Zeroing refers to how you adjust your rifle or pistol to hit their target at their center.

6. Significant Shift on Your Scope’s Reticle from the Center of the Lens

A visible shift on your rifle’s reticle anywhere from the center is a MASSIVE sign of an issue with your scope.

Your rifle’s reticle must ALWAYS be at the central point for accurate firing. This goes for any firearm’s scope.

7. Varying Stiffness in Click-to-Click Feel

Although scope adjustment dials aren’t designed to be moved, that doesn’t mean their dials are stiff.

Any resistance means something is wrong, and your scope may need professional services.

8. Failure to Set Parallax for a Clearer Image

This is when the image you see is not clear despite the lens being clean when you look down on your scope’s sight.

The inability to set parallax for a sharp image does correspond to inaccurate firing from you.

If that’s the case, replace your scope ASAP!

9. Internal Scope Components Rattling

An active hobby or profession such as hunting can cause internal dislodging to your rifle.

I have had gun scopes that have been damaged by recoil, rough weather, rough handling, and accidents.

The tell-tale sign of this accumulated damage is when you hear a rattling noise near the scope’s insides.

Please do maintenance and possibly seek out replacement parts!

10. Wobbly Turrets and Other Loose Pieces

Improper screwing of your rifle’s mounting can lead to inaccuracy of your shot.

This can extend to improper cleaning as even dust build-up anywhere can determine how accurately you shoot.

How and When to Fix Your Rifle Scope

Man holding rifle

After seeing the red flags regarding your rifle scope, Now is the next step; maintenance and repair.

The first assumption is always that it’s simply the shooter’s bad performance. 

However, scopes going bad are just as realistic along with unexpected changes.

SIDE NOTE: Other factors that impede your performance include the right elevation, wind direction, and even your sight quality.

How to differentiate the two is by constantly maintaining your rifle and scope while accurately understanding your own performance.

Always clean off the dust from your scope glass and ensure all the parts are well-oiled. Rifle scopes last LONGER when they are well cared for!

All the while constantly using your rifle, you understand your piece’s shooting performance.

So when you start missing shots on your target or the point of impact is off despite your care, you can tell when your faulty scope needs a REPLACEMENT.

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