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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.

Troubleshooting Tips For Accurate Shooting

Man looking through scope of rifle

Like any machine, vigilant maintenance is required; sometimes, malfunctions happen for no reason.

It will be daunting to learn a rifle scope’s insides, so it’s best to seek an expert’s advice and practice.

Even search out the scope manufacturer brand for advice and replacements for lost or missing parts.

Here are our go-to tips for dealing with dirty scopes and other scope problems:

Dust Your Scope’s Glass Often

Dust off the glass before you clean it with a cloth. When you scrape off dust and dirt, it leaves behind scratches that would lessen your scope clarity.

Microfiber Cloth

Regular cloth, paper towels, and toilet paper are too rough and can scratch your scope’s glass.

It’s better to stick to a specifically designed microfiber cloth, as it’s softer and safer.

Don’t Spray Directly

Although water and eyeglasses cleaner are safe options to clean, spraying directly on the glass of your scope can harm the coating.

Place first on your microfiber cloth before you rub, but too much moisture can damage the scope seals, so use in moderation.

Keep the Cap On

While you clean your rifle, keep the cap ON the scope. The cap protects the scope’s coating and seals from the solvents and cleaners used.

Use Q-Tip Earbuds

Use a cotton Q-Tip earbud to clear your scope’s nooks and hard-to-notice crannies.

Use it with the microfiber cloth to prevent leaving behind cotton wisps.

Use a Lenspen

You can invest in a Lenspen, a specifically designed tool for photographers and hunters, to clean your scope’s glass without liquid. Very affordable and easy to replace!

Here are some additional tips to keep in mind:

  • Leave your scope turrets unscrewed Clean your rifle’s turret as much as your scope; the advice above applies also.
  • Bring a cleaning kit  It’s advised to keep your cleaning kit on hand while hunting to clean and maintain your rifle and scope anytime.
  • Battery cleaning  If your scope is battery-powered, clean it and replace it when damaged or too old.
  • Please don’t overdo it  Over-cleaning your scope can damage it also. So clean your rifle in moderation and track the time you haven’t.

IMPORTANT: Keep the cap on while on the field to prevent environmental damage to the scope glass.

Frequently Asked Questions

Cleaning rifle

To get the most commonly asked inquiries regarding rifle scopes out of the way.

Why is My Scope Not Zeroing?

The screws on your rifle’s mount may be loose or even be overly tightened. Even incorrect cleaning can be another possible culprit.

You can learn more on how to zero a rifle scope at 100 yards through this guide!

How Long Can Scope be Stored?

A scope and their rifle last as long as the construction, materials, and maintenance quality. Quality gear lasts for years and even decades!

What Do I Do With an Old Scope?

Depending on the warranty of the rifle, you can send it back for a warranty repair.

Other options include selling the scope online, experimenting with the scope with another rifle, or donating it to airsoft shooting games.

Are Rifle Scopes Worth this Much Investment?

Yes, a quality scope can provide advantages in shooting your shot in the following ways:

  1. Increases shooting accuracy, and you are more likely to hit your target. Especially for hunting and shooting competitions
  2. Can pinpoint the maximum distance you can fire a bullet into your target.
  3. Can help track how your bullets travel when shooting. Prevents accidents this way.
  4. Helps beginners attempt to hit their target when practicing with their rifle.

Hence why, a good rifle scope needs as much care as your performance. It’s worth the advantages!

What’s That Black Spot in My Scope?

Dark spots on your scope is most likely debris or dust buildup.

Your scope’s glass isn’t completely immune to external elements such, so it’s possible it may accumulated over time.

In unfortunate cases, these particles made their way inside the scope during the manufacturing process.

You can try taking your scope to a professional to have it cleaned or do it yourself.

Why is the Inside of My Scope Fogging?

Similarly, if your scope is fogging, it could be because it has leaked through the glass.

There may be tiny little passages for water or fog to enter the same way dust and debris do.

You can test this problem by submerging your scope in water to see if any bubbles start forming.

Final Words

Looking through scope

Even a slight adjustment to your scope can decide a hit or miss on your mark. But it’s not the end of the world!

Scope malfunction is inevitable. A rifle is like any good machine; its performance does correspond with its maintenance.

So keep this in mind whenever you are in the field or even target practice.

FINAL TIP: If you need help finding the best 500-yard scope, you can check out this guide for reference!

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