H&K Heckler & Koch

H&K Heckler & Koch MR556 Upper Receiver Kit A4 -11″ - M-LOK  This kit includes a complete upper receiver/barrel assembly, allowing Mil-Spec 5.56mm AR-style rifles to be retrofitted...

H&K MR556 A4 16.5″ 5.56 M-LOK Upper Receiver Kit This kit includes a complete upper receiver/barrel assembly, allowing Mil-Spec 5.56mm AR-style rifles to be retrofitted to HK’s piston...

HK Heckler and Koch A4 Complete Upper with Full Auto Ejection Door for HK MR556 The HK MR556 A4 Complete Upper is a superior factory assembly that comes fully equipped with a forward assist and an...

HK MR556 16" Complete Upper Barrel Factory HK MR556 16" barrel, complete with a factory-installed barrel nut, gas block and flash hider. Every component is brand new and meticulously crafted,...

H&K MR556 Slimline Barrel, 16.5" Genuine HK MR556 Slimline 16.5" Barrel.  Non-chrome-lined for match accuracy. Compatible With: HK MR556

H&K HK MR556 A1 Complete Bolt Head Brand new factory German bolt head with all the components to make the bolt head complete. Compatible With: HK MR556 A1/A4

HK German Stripped HK MR556 Upper Receiver New factory German incomplete and unmarked MR556 upper receiver. Compatible With: HK MR556 HK MR223 HK 416 Do you need a matching lower for your...

HK MR556 Operator's Manual

H&K HK MR556 Receiver Take Down Tool This part is the tool used to tighten down the stock movement on the E1/E2 stock. Each tool will be stored in the rear of the E1/E2 stock...

New HK Factory German MR556 Upper Kit with M-LOK forearm Includes: Complete MR556 upper receiver with M-LOK forearm MR556 Bolt group Complete Tungsten Filled HK Buffer HK Buffer Spring One 30 Round...

HK German Un-Assembled/Stripped HK MR556/MR223 A5 Upper Receiver Factory HK MR556 A5 upper receiver. This is the semi-auto MR556 variant. Compatible With: HK MR556 HK MR223 HK 416*** Need a...

HK MR556, MR223 Upper Receiver - BLEMISHED ONLY 1 UNIT AVAILABLE - AS PICTURED MISSING FORWARD ASSIST AND GAS PISTON COSMETICALLY BLEMISHED PARTS ARE FULLY FUNCTIONAL AND SOLD AS IS. THIS PART IS NOT...