I’m often asked about using a PVS-14 as a weapon-mounted night vision device. Short answer: I don’t really recommend it. But, I’m sure you guys want to know a little more than that. First off, we need to understand that night vision, thermal, and lasers are one-trick ponies. They are designed for warfighters who will use them in a professional capacity to smoke the enemies of freedom across the globe. Like all military gear, it starts out as identification of a problem/challenge facing the warfighter and turns into a solicitation for development of product that will solve said problem/challenge (yes, that’s way over-simplified). But unlike the commercial market, the military is usually only interested in solving one problem. They don’t want a product “as seen on TV” that is designed to do everything for everyone because (while it’s a noble goal), the result tends to be mediocre – poor execution of everything. So, it’s really best to have one product that does one thing really well, therefore increasing the chances of mission success and soldier survivability (no; I’m not saying that all issued gear is great. But, I don’t have the time or motivation to write a ten volume series). On the flip side, the commercial products tend to follow market trends. Consumers want products that do everything. This culture clash leads us to some misconceptions about night vision use.
The was designed to be the standard issue NVG for US Army and first saw widespread issue in 1998. As such, it was designed to be on the head 99.9% of the time. A crappy weapon mount was developed due to some initial requests, but warfighters so rarely found a reason to use it, that the piece was often lost to the bottom of dudes’ gear lockers. As an NVG, it needed to be small, lightweight, and handy; all things that lead to a nice goggle, but crappy weapon scope. There is no shock mitigation built into the system (weight/size savings), so the system was “rated” for no more than 5.56x45mm recoil. MILSPEC Night vision monoculars are not designed with weapon mounting in mind because there is no real need for that feature. They are designed with professional end users in mind.
Weapon-mounting a PVS-14 or other monocular is an old civilian construct that harkens back to the dark days (pun intended) before class1 IR lasers existed for commercial purchase. A lot of guys who never served, were never exposed to laser integration or the idea of wearing a NVG on the head while looking through a weapon-mounted optic. Those concepts were and still are, very foreign. So, weapon mounts for NVG’s sort of became a thing. Then, we started seeing the development of “hardened” PVS-14’s and other nonsense that was designed to allow the monocular to be weapon mounted on heavier calibers. This was done by folks with very little real world experience and understanding of NVG application, who responded to consumer demand from equally-inexperienced people, in the form of products that offered a “solution” to a problem that didn’t really exist. Ah, consumerism at its finest.
Let’s say you reject everything I’m going to tell you and have your heart set on weapon-mounting a PVS-14 on a heavier caliber weapon. The first thing to keep in mind is that night vision image intensification tubes work by amplifying existing ambient light. They gather this light through the objective lens assembly (meaning the amount of light gathered is directly proportional to the size of the objective). Light is also degraded every time it passes through a lens. So, when you put your PVS-14 behind another optic, you are already dealing with degraded light. What’s more, the PVS-14’s objective (like all NVG’s) is small for size and weight savings. Remember, this is designed to stay on warfighters heads’ for hours on end while also wearing upwards of 100 lbs of other gear and engaging in some pretty physically taxing activities. So, the objective is designed to give you PID and detection ranges similar to the naked eye’s capabilities in daylight. So, we are talking around 200 yards maximum (on a night with good ambient light levels). I’m not going to get into a discussion of who can see what and various ranges. The US Army AWG has exhaustively gathered this data. The furthest PID capability with a new production PVS-14 on a good night is 174 yards. That would be before you put it behind another optic and lose light. Introducing magnified optics to this mix will further degrade light gathering capability and further tax the performance of the image tube. So, PVS-14’s and other NVG’s are only really suited for use with a 1x red dot (whether you weapon mount or head mount the goggle). So, we are looking at some pretty heavy performance limitations when pairing NVG’s and day scopes. This is why the military uses clip-on night vision devices in front of scopes. When we factor in this data, we tend to limit capability of night vision goggles and weapon optics to red dot and reflex sights. This further suggests we weed out the use of 7.62x51 and other .30 caliber platforms. The main purpose for these weapons is to reach out further than the limited capability of pairing the NVG with the scope anyway. So, a “.308 – rated” PVS-14 tends to stop making sense.
While Gen3 filmed imaged tubes are recoil sensitive, the latest unfilmed tube technology is much more forgiving. But, that doesn’t mean it’s safe to put your unfilmed white phosphor PVS-14 on a .308. The PVS-14 housing is not designed to withstand that recoil and will be damaged. The weapon mount points are the insert-molded threaded insert or around the objective lens locking ring. Either way, the sudden violent recoil transfer will stress and fracture the plastic. We build our TNV/PVS-14’s with a special aluminum locking ring to help mitigate this, but it still doesn’t make it .308-ready. It simply means a ring mount will not fracture the lens locking ring. So, an unfilmed Gen3 tube in a “hardened” NVG monocular housing may be ok for heavier recoil. But factoring the info I already mentioned about system performance at range into the equation, we still need to ask: what’s the point?
Next, the PVS-14 (or any NVG) is not a collimated system. So, you cannot put it in front of a day scope on a rifle. Doing so will still provide you with an image. But, the introduction of another image plane will induce parallax, causing your POI to deviate significantly from your POA. This relegates the NVG to being used behind an optic. Sure, you can weapon mount the monocular behind your red dot. But, we now introduce a damage problem. Even in the near IR night vision setting, your red dot makes plenty of light that your NVG sees. Fixing your NVG behind the red dot for any amount of time more than a minute or two can possibly causing permanent damage to the image tube. The intense, static red dot or reticle will burn in to your image tube because it does not move. Yes, the Gen3 tubes are auto-gated and therefore somewhat protected from light exposure, it still must be within reason. Moving through a lit area while wearing your Gen3 Auto-gated NVG will not expose it to any intense, constant light from a specific source. You can do that for several minutes. But, the constant exposure to an IR or near-IR light source for (even) less than a minute, can cause permanent burn-in. The NV settings on your red dot are designed to be used while wearing the goggle on your head so the light exposure is not constant in the same location.
Lastly, mounting your NVG onto your weapon will deprive you the freedom of an NVG. You have now married your NVG – the device that lets you see in the dark; the whole point of owning night vision, to your muzzle. This means you need to keep your rifle shouldered 100% of the time. I don’t care how strong you think you are; this will smoke you. AND, you are covering everything you observe with your muzzle. That’s a big no-no.
It is actually quite easy and fast to simply keep the NVG on your head (where it belongs) and look through the weapon-mounted optic if you don’t want to use a laser.
Yes, we sell night vision monocular weapon mounts. But, it’s not something we recommend when we talk to our customers. After receiving education on the topic, most guys prefer to forgo the weapon mount. But, some guys just gotta have it, so we offer a QD mount system that allows you to go from a head to weapon mount and back. Sure, there instances where having the goggle on the gun may prove beneficial. But, they are so far outweighed by the benefits of keeping it on your head that they are hardly worth trying to discuss.