Shop our huge selection of MR556 | HK416 | HK 556 magazines, parts, and accessories. Our selection of magazines for the 556 and HK416 come in capacities available in 10 round, 10 round steel, 20 round, 30 round, 100 round drum magazines and so much more, and for any style and variant of firearm.

The HK 556 | MR556 is a direct descendent of the HK416 and is assembled in the USA, composed of US and German components. Like the HK416, the HK 556 | MR556A1 uses a proprietary HK short-stroke gas piston instead of the direct-gas-impingement system that’s found on other AR 15-style rifles. A lot of AR15’s propel exhaust gas into the upper receiver to operate the action. Not the HK 556 | MR556 which has a “closed” piston system, so exhaust gasses never enter the receiver, which means the 556 runs cooler, cleaner, and is more reliable.

We are your primary supplier for HK 556 and HK416 custom parts, Heckler & Koch parts and accessories, and H&K gear in the United States. HKParts is your go-to HKPro since 2002! We love hearing from you and want you to have the best shooting experience, so give us a call if you have any questions about our products.

If you have any questions, feel free to ask our expert staff and they will be happy to assist you in your selection. We care about you having a great shooting experience, so feel free to contact us whenever you need us.

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