• Home
  • FP10.5-5.56M4-10FCR3-KT

Radical Firearms 10.5" 5.56 NATO 1:7 Carbine Length M4 Pistol - 10" M-LOK FCR Gen3 Rail and KAK Pistol Tube

SKU: FP10.5-5.56M4-10FCR3-KT
MPN: FP10.5-5.56M4-10FCR-KT
Manufactured by Radical Firearms
1 Reviews


Out of Stock

NOTE: Limit 1 per household. Quantities exceeding 1 will not allow checkout.


Out of Stock

Items that are regulated by the ATF have restrictions and requirements:
•Your entire order will ship only to a Federal Firearm License holder.
•Current processing time is approximately 14 to 16 days.
•NJ, NY and CA are not able to accept transfers at this time.
•Please contact your local FFL prior to placing your order to ensure they are still accepting transfers. Due to Covid-19 many are no longer open
•A copy of your order/invoice as well as the current FFL license for your local dealer must be emailed to ffl@primaryarms.com.


The Radical Firearms 10.5" 5.56 NATO M4 AR Pistol is law enforcement grade hardware. Crafted with quality materials and covered by Radical’s lifetime warranty, this MIL-SPEC pistol is an outstanding choice for any budget. Just add your favorite iron sights or optic, then head for the range!

The Radical Firearms FCR system is a slim handguard that provides the weight savings you want without sacrificing any of the mounting possibilities you require. This freefloat design offers a monolithic Picatinny rail and plenty of M-LOK attachment points for all your gear.

  • 10.5" 41V50 chrome moly vanadium steel M4 contour barrel
  • Chambered in 5.56 NATO with a 1:7 twist rate
  • M16 cut bolt carrier group with Melonite finish
  • BCG high pressure tested and magnetic particle inspected
  • Standard charging handle
  • MIL-SPEC single stage trigger
  • 1/2x28 A2 flash hider
  • 10" Radical Firearms M-LOK FCR rail
  • Gen 3 rail mounting system
  • Mission First Tactical Pistol Grip
  • Built with KAK Industries Pistol Tube
  • Made in the U.S.A. in Stafford, Texas!


Barrel CoatingSalt Bath Nitride
Barrel ContourM4
Barrel Length10.5
Barrel Material41V50 Chrome Moly Vanadium Steel
BrandRadical Firearms
Caliber Gauge5.56 NATO
Gas System LengthCarbine
Gas System TypeDirect Impingement
Handguard10 in Radical M-LOK FCR Rail
Muzzle DeviceA2 Flash Hider
Thread Pattern1/2 X 28
Twist Rate1:7

WARNING: This Product can expose you to chemicals which is known to state of California to cause Cancer and Reproductive Harm. For more information, see www.p65warnings.ca.gov

Ratings & Reviews

1 review

  • 5 stars
  • 0 reviews
  • 3 stars
  • 0 reviews
  • 2 stars
  • 0 reviews
  • 1 star
  • 0 reviews

Good budget buy but has its issues.

by -

Not a bad buy for the price.
<br>- Great price!
<br>- BCG is pretty good quality for an affordable complete build compared to some manufacturers.
<br>- Upper and lower recievers have very little gap and almost no existent wobble.
<br>- M-Lok rails on the FCR rail are machined to spec.
<br>- Came with ambidextrous selector switch.
<br>- MFT aftermarket pistol grip came with package compared to the basic A2 grip.
<br>- Even though it's a mil-spec upper/lower, some things were out of spec or on the higher end of tolerances.
<br>- It took awhile to find a buffer tube that was thread into the lower due to the super tight tolerances (even the supplied KAK tube fit on there so well that anything bigger would not).
<br>- A2 flash hider was torqued down so much from factory that the crush washer was stuck and would not come off past the threads.
<br>- Castle nut was made of lower quality/soft aluminum and would deform at the part where the armorers wrench would torque so that had to be replaced.