BUIS in humid climates and A/C

[OlongJohnson]

Found an MSDS:

https://www.phillips-safety.com/wp-c...p-SDS-2018.pdf

The only actual ingredient listed is glycerol ("pure" form of glycerin), but it states it is less than 0.02% glycerol. The other 99.98% of the contents are "trade secrets."

Other reading I've done suggests that glycerin is the basis for most anti-fog products. If the concentration is really that low, I could see some product variability due to less than complete mixing explaining the fairly large number of reviews that say it doesn't do much of anything.

I have sent an inquiry through Leupold's contact form. Will post up if I get a response.

[Coyotesfan97]

I don’t remember my Aimpoints, my PMO, or a scope lens fogging on me. My glasses are another matter. During the Arizona monsoon season I’ve had my lenses fog up immediately. I’ve also had them fog up under my cap brim from my breath.

[NH Shooter]

In the "Oh, shit!" scenarios we are envisioning, I feel the express rear would be faster and accurate enough versus an aperture. (I leave the large aperture up by default)

https://www.xssights.com/Products.aspx?CAT=8279

Huh, I've never seen these before - I like!

I'm currently using the Midwest Industries offset BUIS and like them. The rear has a single mid-size aperture which makes acquiring a sight picture reasonably quick, but probably not as quick as the XS setup. With the 3 - 9x optic I'm running, the XS set could make more sense for the under 25 yard distance.

[OlongJohnson]

Found an MSDS:

https://www.phillips-safety.com/wp-c...p-SDS-2018.pdf

The only actual ingredient listed is glycerol ("pure" form of glycerin), but it states it is less than 0.02% glycerol. The other 99.98% of the contents are "trade secrets."

Other reading I've done suggests that glycerin is the basis for most anti-fog products. If the concentration is really that low, I could see some product variability due to less than complete mixing explaining the fairly large number of reviews that say it doesn't do much of anything.

I have sent an inquiry through Leupold's contact form. Will post up if I get a response.

Got a response.

I have not seen tests as to how those products affect our lenses. We have tested and recommended for years a product called Kleer-Vu. it has been tested in our optics lab to have no ill affect on our glass.

Looked it up. The reviews on Amazon have a similar number of people saying it did virtually nothing.

I'm thinking hard about just buying some glycerin at a pharmacy and trying that.

[TCB]

I worked in the Rio Grande Valley for a few years and had both an Eoturd and an Aimpoint micro on my issued rifle at different times. In and out of an A/C’d vehicle multiple times a shift in the insane humidity / heat that is the RGV. Never had an issue with the optic lenses fogging (eye pro is another story). Have had rain drops, mud and various other debris partially obscure the lenses at different times and a quick wipe to the rear lens with your thumb and all was good (easier and more effective on an Aimpoint than the other one). As long as the rear lens is clear you have a dot and can make a shot with both eyes open. It only takes a fraction of a second to check and rectify if you use your support hand (it’s already right there moving past the optic when you charge the weapon).