Lasers on guns is nothing new. Most require a Picatinny rail to mount said laser or it is somehow integrated into the gun like Crimson Trace’s line of grip lasers. However Viridian has gone in a different direction with their latest and made a laser that actually fills a gap in the industry for low profile lasers. The HS1 finger stop has an integrated green laser.
HS1 Finger Stop Is Not A Hand Stop
Even though Viridian calls the HS1 a hand stop, it is actually a finger stop. As per Arisaka Defense on their own finger stop:
Unlike a hand stop, which most people position at the rear of their support hand, the Finger Stop is ergonomically designed to be located between your index and middle fingers. This typically places it further forward on the handguard, which also means it doesn’t get in the way when transitioning to kneeling or prone shooting positions, where most people move their support hand towards the rear.
Additionally, the Finger Stop functions well as a forward limit to prevent your fingers from slipping off shorter handguards onto a hot barrel or suppressor, and as a barricade rest.
I concur with Arisaka, the Viridian HS1 is a finger stop because you do not put your whole hand in front of it like a typical hand stop. Nor is it in front of your entire hand like other styles of hand stops such as the one that came with the CZ Scorpion Evo or the KSG.
The HS1 mounts to M-LOK with just two screws. It only requires one and a half M-LOK slots to mount it.
As you can see above, the HS1 battery compartment is the finger stop and you can see the small green activation button just behind and below the forward M-LOK mounting screw.
I wanted the HS1 specifically as a low profile laser for my H&K SP5. I used a Midwest Industries M-LOK handguard. As I said before, the HS1 finger stop is not a hand stop. Look at my hand position below. I position the HS1 finger stop between my index and middle finger.
If I try to use the HS1 finger stop as a hand stop, my hand will cover the laser emitter aperture and block the laser.
With the HS1 finger stop on the Midwest Industries M-LOK handguard, I can c-clamp the barrel. I am even able to position the SureFire tape switch on the side and activate it with my fourth finger. So now I can maintain light and laser discipline by simply squeezing my support hand to activate and release to turn them off. I can also activate the laser or light independently.
The HS1 design makes it completely ambidextrous. So if you are left handed, you do not need to reposition your support hand to activate it. Just grip and squeeze.
Mounting The HS1 Finger Stop On an SP5K PDW
The H&K SP5 handguard has ample real estate for lights and lasers. But the SP5K PDW (MP5K) has a much shorter barrel so the handguard leaves you with very little options for lights and lasers. I used the Magpul MP5K SL Handguard for my SP5K. I chose this over the Midwest Industries M-LOK handguard because the thenar of my support hand touches the trunion and the Magpul handguard covers that up. Given the position of my support hand while utilizing the HS1 finger stop, I would need that extra coverage.
However, the HS1 finger stop does not fit the Magpul SL handguard without modification, the laser aperture is a smidgen too long. Since the HS1 is so low profile, the laser aperture is right up against the handguard so the integrated hand stop in the SL handguard is too long and it blocks the laser. I had to drill and cut a slot for the laser to shine through.
Shooting With The HS1 Finger Stop
The HS1 finger stop is a 5mW visible green laser. This is eye safe but at night it is very bright. So bright in fact that you can see the beam through the air.
The ergonomics of the HS1 finger stop make it very comfortable and easy to activate.
Here is the HS1 mounted on my SP5 shot at night. There was a near full moon out so you do not see the laser beam as easily.
Final Thoughts On The HS1 Finger Stop
The HS1 retails for $179.00. Considering its uniqueness and low profile design, I say it is a must buy if you want a laser on a large frame pistol or SBR. Sure you could use it on a rifle as well. I love how the laser aperture is just below the handguard so your laser to bore offset is greatly reduced. Due to the HS1 design there is only one way to really grab the handguard and activate the laser. However if you had to use the laser on a barricade you could position your support hand on the barricade and rest the HS1 on your support thumb to activate the laser. The HS1 button is momentary only. There is no constant on mode. I would have liked it more if Viridian programed the laser so a double tap would force the laser to stay on. The HS1 is powered by a small 1/3N sized battery and I have not been able to find any information about the battery life. This sample came with just a quick start guide and there was no mention of battery life in it. The HS1 is only offered in green visible laser at the moment. I hope Viridian comes out with an infrared model although the green laser works well under night vision. For more information go to Viridian’s website.
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