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Freedom Ordnance - FM-9 9x19NATO Belt Fed AR-15/M-16 Upper Receiver - 11" Barrel



This is the 11" barreled version.

We at PK Firearms are proud to announce we are now carrying the Freedom Ordnance, FM-9 9×19 Nato Belt Fed upper. Over a year in development and 10,000+ rounds in testing have been done by Freedom Ordnance, to bring you the world’s first 9mm belt fed!

FM-9 - 150 round belt bag


150 round belt bag

Top is made from machined billet aluminum and has a nitrided steel retaining flipper where the belt comes out of the bag for better feeding control. Belt bag is made from 900 denier fabric with a heavy duty zipper.

FM-9 links – Bag of 1000


Our FM-9 9mm links are made from high carbon steel heat treated with a manganese phosphate finish. Sold in quantities of 1000.

FM-9 - 6" Barrel upgrade kit


This kit upgrades your unit to use a 6″ barrel. Includes one 6″ barrel, one 4″ quad rail, and one 9″ 7/64 T Handle hex wrench.

6″ barrel is made from 4150 chromoly steel. QPQ nitride finish

4″ quad rail is black anodized billet aluminum with Picatinny rail system.

Knights Armament - SR-15 E3 Mod2 CQB 14.5" - Complete Upper


The newest redition of the KAC SR-15 E3 Carbine MOD 2 is designed to be a premium upper receiver with KAC's expertise in producing top tier rifles and components for the military and discerning consumers.  

This upper receiver is lightweight, accurate, and durable.  

The proprietary gas system, rail system, and Bolt/Barrel design ensures that this upper can deliver superior performance in this lightweight yet durable package


Rock River Arms 16 inch QMC Upper


The Rock River Arms 16 Inch QMC Upper features a Rock River Arms 16 inch H-Bar barrel chambered in 5.56 NATO with a 1:9 twist rate and 1/2-28 threaded muzzle, Mid length gas system, RRA TRO standard handguard with 2 short rail sections and one standard.  Built by Rock River Arms on an RRA forged A4 flat top re

Rock River Arms 7 inch A4 pistol upper


The Rock River Arms 7" Inch A4 pistol Upper features a Rock River Arms 7 inch Chrome Moly barrel with a 5.56 Nato chamber, 1:9 twist, pistol length gas system, and a 1/2-28 threaded muzzle.  Built on a Rock River Arms forged A4 flat top receiver with a low profile gas block, TRO pistol free float rail, and an A2 flash hider. Included are 3 accessory rails for the hand guard.

Complete with Rock River Arms AR-15 bolt carrier group and forged charging handle.

.204 Ruger Varmint A4 Complete Upper


.204 Ruger Varmint A4 Complete Upper 

The Rock River Arms .204 Ruger 20 Inch - Varmint A4 upper features a Rock River Arms 20 Inch fluted stainless steel, air gauged, cryo-treated bull barrel chambered in .204 Ruger with a 1:12 twist and rifle length gas system.  Built on a Rock River Arms forged A4 flattop receiver with a Rock River Arms TRO-STD handguard and a .936 low profile gas block.

Complete with RRA bolt carrier group and RRA charging handle

Rock River Arms 6.8 SPC Coyote Carbine Upper Half SPC0592


Rock River Arms 6.8 SPC Coyote Carbine Upper Half SPC0592


Rock River Arms Fred Eichler Predator Upper


Rock River Arms Fred Eichler Predator Upper

Caliber: .223 Wylde

Upper: Forged A4

Barrel: 16 inch Stainless Steel, 1X8 Twist, Cryo Treated

Muzzle: Tuned and Ported RRA Muzzle Break

Charging Handle: BCM Gunfighter Mod 4

Handguard: RRA Fred Eichler Series Free Float