A rifle scope is a crucial hunting or shooting accessory. It helps to improve accuracy and make long-range shots easier.
However, stuff happens, as they say, and sometimes one of the lenses on the scopes gets dirty.
But there’s a difference in getting mud splashed onto the lens and just having dust collect on it while it’s in storage. We’ll talk about both.
The most common mistake people make when cleaning a riflescope is that they’re too casual about it. They just grab their shirt sleeve or a paper towel and go to town; don’t do this.
The second mistake people make when cleaning a riflescope is that they’re not casual enough about it, and worry so much about damaging the lens coatings that they leave the scope dirty for too long.
What Is the Best Way to Clean a Rifle Scope Lens?
Start with a basic fine-hair lens brush and get rid of any loose dust that’s sitting on the lens. If there is still more to clean, you can use the soft pad that usually comes with the fine-hair brush.
If there is still more after that, you can apply a lens cleaning solution or 90%+ isopropyl alcohol and a microfiber lens cloth.
There’s a phrase I’ve heard many times working with different law enforcement clients: minimum necessary force. This very much applies to scope lenses.
Only clean it as much as you need to to get a clear sight picture. Even the recommended forms of lens cleaning will eventually wear down on the lens coatings.
How to Clean a Rifle Scope Lens: The Step-by-Step Process
Regardless of whether cleaning scope lens seems daunting or simple, there is a pretty standard process you should follow when you want to get that scope spic and span.
Here’s what you need to clean a scope lens:
- A soft-bristle lens brush or compressed air blower
- A cleaning solution
- A microfiber cleaning cloth
Here is a step-by-step guide on how to clean your scope lens:
Step 1: Brush or Blow
Before applying any gun cleaning solvents to the lens, it is important to remove all the dust and dirt, or debris that may be on the surface. You can use a soft-bristled lens brush or a compressed air blower to gently remove any loose particles.
Make sure to be gentle when brushing or blowing the lens to avoid scratching the surface. Hold the rifle scope upside down and gently brush the lens in a circular motion or blow away any loose debris.
You don’t have to hold it completely upside down, you just need to have it in a position where the dust can actually fall out after you loosen it.
There isn’t much difference between using canned air or a brush, just make sure the pressure on the air isn’t very high. One of those little squeeze-bulbs with a nozzle at the end that you operate by hand is perfect.
Your big industrial air compressor that goes up to 2000 PSI, though, not so much.
Step 2: Apply Cleaning Solution
Once the loose debris has been removed, it’s time to apply the lens cleaning solution. Apply a few drops of the cleaning solution onto the cloth, or you can drop the solution directly on the lens. Once again, “minimum necessary force”. Do not use more solution than is needed to cover the lens, unless there is hard debris (like mud) you need to loosen.
There’s a little disagreement here, and some shooters are leery about dropping isopropyl alcohol directly onto their lens. There is no meaningful difference between putting it on the microfiber cleaning cloth’s inside first and dripping it directly on the lens.
Either way, the cleaner gets on the lens, and there isn’t any risk that the little tiny bit of cleaner that you’re using is going to find its way inside your scope.
If that little tiny bit of cleaner does get in your lens, your lens is clearly damaged because it shouldn’t be letting just about anything in at all.
If you have mud caked on the lens, you shouldn’t just chip it off. You should apply cleaner directly to it in order to soften it before moving onto the next step.
Step 3: Use Microfiber Cloth
Using a microfiber cloth, gently wipe the lens in a circular motion. Do not apply too much pressure or scrub the lens vigorously as it can scratch the lens. Ensure that you cover the entire lens, including the edges.
This is the part that a lot of people get nervous about, and it’s understandable. It is correct that the lens cloth itself will not scratch the lens, but the little dirt and rock particles that you’re pushing around absolutely could, so you want to be gentle and avoid pushing down onto the lens.
Work the cloth horizontally to push things out of the way while holding the scope upside down if possible, or as close as you can get to it.
Step 4: Allow to Dry
After lens cleaning, allow it to air dry for a few seconds. Avoid wiping the lens with a cloth or tissue to dry it as it can cause streaks or scratches. Once it is dry, you can inspect it to see if there are any spots or streaks left.
It really doesn’t take much time for the lens to dry. This is partly because you haven’t applied very much solution and partly because you soaked up most of it with the cloth. Either way, let it dry and then go ahead and look through it. Theoretically, it should be as clear and bright as the day you bought it.
Step 5: Repeat if Necessary
If there are still spots or streaks left on the lens, repeat the process until it is clean. If the lens is still not clean after several attempts, there’s a chance that whatever is gunking it up is on the inside.
If that’s the case, you may want to check the warranty on the scope and see if you can still get a refund, because it shouldn’t be letting anything in there, let alone solid particles.
What Not to Do When Cleaning a Riflescope Lens
When cleaning a scope lens, there are certain things that you should avoid doing to prevent damaging the lens. Here are some of the things you should not do when cleaning scope lenses:
- Do not use regular cloths or paper towels to wipe the lens as they can scratch the lens.
- Do not use harsh cleaning agents or solutions as they can damage the lens coating. Only cleaning solutions designed for lenses (cleaners for glasses work great, as does >90% isopropyl alcohol) should be used on rifle coated lenses.
- Avoid using water if you can. I won’t take as hard a stance on this as some folks, because I’ve seen scopes cleaned with a microfiber lens cloth and just regular bottled water and it worked great. That said, water can take longer to dry and is more likely to leave spots on the lens after lens cleaning. Water is better than nothing, but get something better if you can.
- Compressed air is a fine replacement for using a brush, but make sure not to use very high of PSI to do it. Generally speaking, I think your best bet is some kind of hand pump, whether it’s designed for inflating balls, bike tires, or specifically designed for cleaning lenses. Using lens caps will avoid dirt on scope.
At the end if you wish to know how often should you clean your gun & scope, read this!
If your scope is not clear, it could be due to a number of reasons. The most common reason is that the lens is dirty or has a foggy residue on it. Other reasons could be that the lens is scratched or damaged, or the internal components of the scope are faulty.
A scope can fog up due to changes in temperature and humidity. When warm air meets a cold surface, it can cause condensation to form, resulting in a foggy appearance on the lens. This is especially common when moving from a cold environment to a warm environment or vice versa. This type of fogging is normal and shouldn’t be much of a concern. However, if the rifle scope is not properly sealed, moisture can enter and cause the lens to fog up from the inside.
The best way is to buy a lens with fog-proofing. Most multi-coated optics have a coating included that reduces external fogging from temperature changes, and every reputable scope company seals their scope so that nothing can get inside.
Cleaning the lens of a rifle scope is crucial to ensure that it remains in good condition and performs optimally. By following the step-by-step process outlined in this article and avoiding common mistakes, you can maintain the clarity of your rifle scope lens and improve your shooting accuracy.
Remember to always use a gentle approach and try not to use harsh chemicals or abrasive materials when cleaning your rifle scope lens. There are ways you can be too casual about cleaning your dirty lenses and ways you can be not casual enough. At the end of the day, cleaning rifle scope lenses isn’t much different from cleaning other professional optics.