Over the last 6 months, I’ve run the Primary Weapons Systems as my main rifle and it’s been an interesting ride. When I first started looking at PWS line up of guns, I was really curious how the long stroke gas piston system worked so I ordered the MK116 MOD 2-M rifle. The rifle may look like an AR-15 but apart from looks, the gun is almost entirely different from your standard AR rifle.
Right out of the box, the PWS MK116 MOD 2-M came well equipped compared to most rifles. The rifle is chambered in 223 Wylde and has a 16-inch barrel. Standard features include a Bravo Company USA Gunfighter stock and pistol grip along with a Radian Raptor charging handle made specific for PWS’s long stroke piston system. The 15-inch handguard is made for the rifle and has a combination of M-LOK and Picatinny rail sections for easy placement of accessories. My rifle came with a 16-inch barrel and unloaded with no accessories is just under 7 pounds. With my red dot and flashlight, it brings it to just over 7 pounds. For a long stroke piston rifle, the gun seems really well balanced. Gladly, the rifle doesn’t seem front heavy like I thought it would.
The MK116 MOD 2-M has a 1:8 twist barrel with a 3 position gas block for various ammo pressures and suppressed settings. The forged upper and lower receivers look visually different from most ARs on the market and I really like the look of the gun. With the long stroke piston system, PWS have deleted the forward assist off of the gun. I don’t see that necessarily as a bad thing and it gives the gun a different profile from others like it. The PWS FSC556 is a hybrid muzzle brake and flash hider that does a nice job. As a result, the gun shoots really flat with little to no felt recoil. The MSRP of the MK116 MOD 2-M is $2,049.95. It may not be the cheapest option but its definitely a unique system.
Like I said earlier, I’ve made this rifle my primary range rifle when running drills and taking classes. So far, I have roughly 2,200 rounds through the gun and haven’t had any malfunctions to date. One thing that surprised me about the rifle is how soft the gun recoils. There is nearly zero felt recoil depending on the gas setting the rifle is set at. I thought since it was a long stroke piston system it would have more felt recoil but I was happily mistaken.
When the rifle was new, I put a Vortex Strike Eagle 1-6 on to see what kind of accuracy I could get out of the rifle. At 100 yards I was averaging 1.25-1.5 MOA depending on the ammo. To test accuracy I was using 69gr Federal Gold Medal Sierra Matchking. It may not be the most amazing groups I’ve ever seen out of an AR, but for a long stroke piston system, I was happy with the results. I loved the clean single stage trigger that came standard in the gun, it had a short audible reset that was really enjoyable to shoot.
The lower receiver has a bit of a flared magwell so doing reload drills are very easy and the subtle difference makes a big difference. A bolt release button on the right side of the lower receiver is a nice addition. It made getting the gun back into action much quicker with a little practice. The rifle shipped with a translucent Lancer magazine that worked well with the gun, I ran a number of different magazines through it, and each one fed without issues.
Cleaning and Disassembly
I went 2,000 rounds without cleaning the PWS and it didn’t seem to be affected by the lack of lubricant in the system. With the PWS rifle being a completely different system than most AR systems, I thought it would be much harder to disassemble than it really was. The bolt carrier group is similar to a standard AR DI or piston system. The PWS has its long stroke piston attached where the gas carrier key would be on a standard AR. The long stroke gas piston brakes down into two pieces so it’s fairly easy to handle and clean.
Even after 2,000 rounds, the piston and carrier were really easy to wipe down and I didn’t have to scrub carbon off like I expected. The system seemed clean for the most part which was a definite plus for cleaning. The MK116 MOD 2-M isn’t difficult to put together by any means, but users have to make sure to guide the long stroke piston in correctly. Once I took a second to look at how to assemble the rifle, it was really easy and I didn’t have an issue.
When I first got the rifle, I was excited to test out the long stroke gas piston. Even after six months, I love how soft shooting and controllable the rifle is at the range. The MK116 feels lighter than expected and can transition targets without much effort and adds to the experience. Personally, I think the PWS MK116 is a jack of all trades without many drawbacks. Some people may not like the fact it has no forward assist but I don’t mind that. The only negative is the open brake when shooting prone from a barrier but that’s a very small annoyance in the bigger picture.
If you’re looking for a go to hell and back rifle I would seriously consider this rifle. It’s low maintenance and with the adjustable gas block, it can reliably run all kinds of ammo. The MK116 MOD 2-M is in the higher tier price bracket but PWS has developed a rifle that reliably implements the long stroke gas piston system made famous by the AK variants around the world. I think it’s a mashup that works great and makes the AR platform look sleek as a result. Let me know what you guys think of Primary Weapon Systems changing things up with their long stroke gas piston system. If you have any questions about the rifle or shooting, in general, send me a message on my Instagram @fridgeoperator. Stay safe out there.
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