HK MR556A4 Upper Kits Now Available
Heckler & Koch has new upper receiver kits available. H&K is selling the uppers from the new MR556A4 rifles for those who don’t want to buy a complete gun. They are fully compatible with any standard AR lowers, including prior generations of the MR556.
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These new A4 uppers include adjustable gas blocks and all other features found on the complete A4 guns. This includes the extended charging handle and cold hammer forged barrel as well. The handguard has MLOK slots and a picatinny rail that runs along the top, and is fitted with QD sling cups.
The MR556A4 uppers come in two lengths, a 16.5-inch model and an 11-inch model. Both have MSRPs of $2499, which includes the upper, BCG, buffer, and recoil spring.
From the manufacturer:
“Heckler & Koch USA announces the availability of MR556 A4 upper receiver kits for sale at HK dealers nationwide. The MR556 kits are available in 11” and 16” barrel lengths and carry the same lifetime barrel wear warranty as a complete MR A4 rifle.
These are complete uppers with all components, including the assembled upper receiver, bolt carrier group, gas piston assembly, barrel, and adjustable gas regulator. They also are compatible with most common AR 15 / Mil Spec lower receivers.
The MR 556 is HK’s commercial variant of the legendary HK416. Its short stroke gas piston replaces the direct gas impingement system of a traditional AR pattern rifle. It runs longer and more reliably, with less maintenance and much less wear on internal components when compared to a DI system.”
AKA @fromtheguncounter on Instagram. Gun nerd, reloader, attorney, and mediocre hunter.
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I think most all piston systems are overrated. They are heavy, they are dirty, they are expensive, and when you lose interest they are useless. I'd rather put a match barrel in a DI gun and fine tune it how I want it and be lighter, more accurate, cleaner and more flexible.
External gas piston ARs are overrated, especially when they cost a fortune yet couldn’t be bothered to be designed to use a folding stock.
Piston gun fanboys are a special kind of stupid.
I totally agree with Frederick Douglass, Joe is incorrect, very much so. Piston systemsare inherently much cleaner running than DI systems.