Repeated Cleaning of Scope Lens with Lens Wipes

If done properly and gently it should not be a problem. I keep scope covers over my lenses so cleaning is very rare. Had my Leopold scope for over 25 years

I use them all the time, but I usually try to blow any dust off first so I don't grind grit or dust into the lens. I use them on my eyeglasses, scopes, binoculars, cell phone screen, yada, yada. They are safe if used reasonably.

As an avid photographer, we use a squeeze blower with soft brush to remove as much dust as possible before using a zeiss wipe. That being said, most lenses nowadays have some form of coating on lens to protect it from scratches.

i sure wouldnt do it unless necessary, thats why they come with caps ... come to think about it i dont think ive had to clean a scope lens in .... maybe 15 years, and i got probably 20 of them .. i would guess unless your in the field and get the gun wet would probably be the only reason they would get smudged to the point they need to be wiped ..

reading up on those picky azz camera lens boys' forums that convinced me to do as Ranchibi says 

I've got some nice scopes and being out west in a silty cinder dust area I've developed my own method which some might sneer at but it works great.

First I take the rifle to the sink and squirt the lenses off "good" with a light spray from the spray nozzle and try to keep the water off the gun by turning it upside down. You can follow up by using distilled water in a spray bottle but I don't do that. Doing this removes the grit in the threads and inside of the metal by the glass.

Next I get a cotton ball and put a drop of dawn dishwater liquid, start scrubbing lightly from the middle of the lense and working out to the edge with light pressure. This gets the grease off the threads too and that grease of course attracts grit.

Rinse the lenses out in the sink again with the spray nozzle. If you are concerned about hard water you can follow up again and rinse with the distilled water. Some people like to put in a drop of rubbing alcohol which makes the water evaporate off quicker. 

Then take a clean terry cloth towel to wipe off excess water by starting from the middle of the lense and working outward. I just use a brown wash cloth from the bathroom. 

If you have a super cheap scope you may not want to try my method because the water could get into the scope. I haven't had any problems yet with any of my scopes yet whether cheap or not so there's that.

I’ve cleaned hundreds of camera lenses after almost 50 years as a camera repairman. If you feel you will be daily cleaning your scope and don’t want to cause any damage I would suggest the basic industry standard for lens cleaning. First blow the lens off with a light blast of air from a low pressure source ( we used a dental air compressor to give you an idea of low pressure), a quality lens cleaner like Kodak or Zeiss and Kimwipes to rub on the lens in a circular motion. Kimwipes are a specialty cleaning wipe for delicate surfaces that are packed in a box like Kleenex and should cost $5-7 a box bought individually (we bought by the case). Zeiss lens wipes are great for occasional use but the material is too harsh for daily use and the cleaner in them has too much alcohol to be effective on anything but oil based smears. Good lens cleaners are water based with a soap and alcohol mix. You need water and soap to clean a mud smear or similar dirt. Alcohol will clean grease and oil (fingerprints) plus add a drying agent. The Dawn dish soap idea isn’t far off. At one time we mixed water, dish soap and alcohol to make lens cleaner but it became too hard to get dish soap that wasn’t loaded with extra stuff that caused streaks. The Equate lens cleaner from Walmart isn’t bad but for the extra $2 for 8 oz buy the Zeiss. I don’t know how hard it is to get Kodak lens cleaner in 16 oz containers now that I’m retired since I still have over 2 pints left to go before I will need any more. 

The most effective way I have found is a lens pen. They have retractable brush on one side and a special little sponge on the other.