HK416, MR556 Piston Rod, Complete Assembly
HK416, MR556 Piston Rod, Complete Assembly
35 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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Great quality
Quality is absolutely stellar. Nefarious arms nails it everytime
Let customers speak for us
from 62 reviewsA hard to find item which you had in stock. Order placed in the am and shipped the same day. Quality parts and outstanding service!
Shipped same day and was exactly as described! Yall are awesome! Cant wait to buy more stuff!
Heavy duty and well machined.
This company is great! Marvin is an artist, orders sometimes will take a while but rest assured when you do get it, it will be perfect, so if youre a potential customer, be patient. It will be done
I enjoyed all the products so far. I plan to purchase more products in the future, keep up the good work!
I used this tool to build a Nefarious Arms A3 IAR barrel on an MR556 upper, and it was absolutely perfect for the job. It easily held under the required torque specs with zero barrel shift. More importantly, it eliminated any worry about shearing off the index pin, ensuring near-perfect timing after installation.Before this, I attempted to use a Midwest Industries Reaction Rod but found way too much play. The MR556 platform demands tight tolerances, and a generic reaction rod simply doesn't offer the precision needed. Because this tool is made specifically for these barrels, the fit is exact. If you are doing an MR556 build, this is the tool you need.