A while back, Covert Optics had a blowout sale on the Thermx HS1 thermal handheld scanner. The HS1 is no great shakes in terms of thermal performance – 160×120 resolution, 4x magnification, and a 9hz refresh rate. However, at $100-$200, it was a way of getting some thermal capability at a very low price, which is nothing to sneer at, and also takes RCR123As, which is very handy.

One of the neater capabilities that the HS1 has is the ability to be used as a thermal sight with a reticle. The adjustments are extremely coarse due to the low resolution of the screen – a bit over half an inch per digital “click” at 10yds – so it’s a pistol range solution at best. But its small size also lends itself to that application.

My initial thought was to use it with a 1911, but I was unable to figure out a suitable fixed mounting solution. I then realized I had a spare 22/45 upper, and that this would be a pretty good host for this optic. I bought an inexpensive 30mm low profile mount off Amazon, but any cheap 30mm ring would probably work.

Besides turning the reticle option in the menu, picking your favorite, and zeroing it (I used a laser boresighter), you want to go into the sleep menu and disable dimming and sleep. The HS1 has what I assume is a mediocre-to-bad NETD sensitivity, and you don’t want your sight going any darker than it has to. Similarly, make sure brightness is high.

When I took it out to the range on a summer day recently, I had mixed results. It did seem to maintain zero, but it was really hard to spot the steel due to the poor NETD. Similarly, even when I slapped some toe warmers on the steel, it didn’t do much to improve visibility because the ambient temperature was so high. I suspect I would have better results in the winter. The poor refresh rate was problematic, but not a deal breaker unless you’re looking for a really high performance solution.

All in all, it was an interesting experiment, but I suspect that this is a case where the raw technical limits of the HS1 (screen resolution, thermal resolution, and NETD) conspire against it a little too much. As a handheld solution, though, it’s really quite convenient and useful, and might make a solid addition to a bug out bag or a plate carrier.