HK416, MR556 Piston Rod, Complete Assembly
HK416, MR556 Piston Rod, Complete Assembly
67 in stock
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Genuine HK performance — accept no substitutes.
The HK416 / MR556 Piston Rod Complete Assembly is a factory-original Heckler & Koch OEM part, engineered to the same exacting standards trusted by professional operators worldwide. Designed for flawless reliability and smooth operation, this piston rod assembly keeps your HK system performing exactly as intended — clean, consistent, and dependable.
Key Features:
- Factory OEM HK part — genuine Heckler & Koch manufacture
- Precision-machined and heat-treated for exceptional durability
- Designed for clean, consistent gas system performance
- Compatible with HK416 and MR556 platforms
- Complete and ready to install — no fitting required
Upgrade or replace with confidence. Order your genuine HK416 / MR556 Piston Rod Complete Assembly today.
Compatible with:
- HK 416
- HK MR556
- HK 417
- HK MR762
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Let customers speak for us
from 12 reviewsJust outstanding work on this barrel. The amount of attention to detail and precise on the dimples. Everything else is great too, packaged great for shipping. It's like a fine work of art. Can't want to put it to the test on the range and test out different ammo types for see how it groups. Great work guys!
Wasn’t disappointed. The fit and finish of the 14.5 hk416 are great. Top notch!
Great products offered with fair pricing and excellent finish. Shop with confidence that you are getting quality items.
Excellent fit and finish. My front sight base mount and bayonet lug fit was spot on. Getting it assembled and waiting on a few more parts to hit the range.
Fulfilled my order quickly and packed it nicely. A+ to the folks at Nefarious Arms.
I havent got a chance to shoot it yet, but the barrel looks phenomenal, always putting out great work at Nefarious Arms. A+ the chrome is shiny and the exterior finish is impeccable.
The shipping was lightning fast, and the website was easy to navigate. Nothing more to say, it was a great shopping experience :)
Great gas block. The fit and finish were exemplary, and the knob was nice and movable, making it easy to turn with the tip of a bullet from various angles. Gassing on a brand new MR556A1 barrel was perfect with the factory-installed 1mm vent screw, giving 1:30-2:30 ejection on N and 3:30-4:30 ejection on S with a B&T SRBS installed. Wonderful product and a great price for everything you get!
Very nice finish, excellent fit. I like the pin locations have dimpled centres, makes drilling that much easier. Having both the HTX and Nefarious I prefer the latter.
These are pristine, brand new, unmarked German A3 stripped uppers. They’ve never been assembled. The finish is perfect. Well worth the money.