Shipping to California
- Status: Complete upper with a barrel. Not a serialized firearm, but we ship it to a licensed dealer only.
- Delivery: Ships to WBT in La Mesa or to the California gun store you choose; select your dealer at checkout. Not shipped to home addresses.
- Learn more: Featureless or fixed magazine: which fits your build · FAQ
About this upper
Heckler & Koch H&K MR556 A4 (11") Complete Upper Receiver is an upper receiver chambered in .223/5.56 with an 11" barrel. Finish: Black.
Manufacturer details
This kit includes a complete upper receiver/barrel assembly, allowing Mil-Spec 5.56mm AR-style rifles to be retrofitted to HKs piston and pusher rod system. This system utilizes a piston and a pusher rod in place of the gas tube normally found in AR15/M16/M4-style rifles. This closed system virtually eliminates the malfunctions that are common in direct-impingement gas systems, since hot carbon fouling and waste gasses are not propelled into the receiver area to operate the action. This is the same key feature critical to the success of the HK416 used by elite military and law enforcement customers. Upper will ship in HK Soft case.
Specifications
- Brand: Heckler & Koch
- Caliber: .223/5.56
- Barrel: 11 in
- Finish / color: Black
- Fits: AR-15
- Manufacturer part #: 51000385
- UPC: 642230270220
Buying from WBT Guns
- Delivery: Complete uppers ship to a licensed dealer only. Free pickup at our La Mesa store, or select the California gun store you want it sent to at checkout.
- Payment: Pay in full, put 50% down with the balance due in 14 days, or finance with Credova.
- Questions: Call (619) 667-9453 or email sales@wbtguns.com. FAQ
WBT Guns is family-owned in La Mesa, California, and has shipped parts and receivers to California buyers since 2012.
A note on accuracy. We work hard to keep every listing correct, but specifications, images and compliance details come from many sources and can contain errors or change without notice. Images may show a configuration that is not California-legal. If a detail on this page matters to your decision, call us and we will confirm it against the actual firearm before you order. The compliance information here is general in nature and is not legal advice; California and local laws change, and the configuration described is confirmed at the time of sale. All sales are subject to applicable federal, state and local law and to the buyer's eligibility to purchase.
