LE Colt M4 + AR15 Gun Build

Today we’re featuring an awesome M4 / AR15 build from @squeaky_steps. This is a LE (law enforcement) Colt M4 with an FBI Hostage Rescue Team Upper 11.5 inch colt heavy barrel, a Geissele Mk4 Federal Rail, Troy Backup signts, Aimpoint T2 with a Larue Mount and a surefire M951 light with Cloud Defensive LCS.


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How to build a LE Colt M4 / AR15 like this.. 

1- Rifle

The M4 is just a military spec, this weapon is an AR-15 platform.

Buy the Colt M4 / AR-15 Caribine at 1800Guns and Ammo.

Price varies, click image for updated price on 1800Guns&Ammo







2- FBI / HRT 11.5 Heavy Barrel

When it comes to this barrel, dig around a bit. Here’s one site that offers them.







3- Geissele Mk4 Federal Rail

You could also pick this up in “Sand” color if you really wanted.

Click image to check price







4- Troy Backup Sights

5- Aimpoint T2 with a Larue Mount

Huge fan of this build, but the one part I would change is the Aimpoint T2 / Larue Mount. Instead of this hardware – I’m going with the Aimpoint Red Dot with QRP2 Mount (comes as a set).

Check Amazon pricing of Aimpoint Red Dots..

Aimpoint Red Dot Sight / Mount








6- Surefire M951 light w/ Cloud Defensive LCS

Buy the Surefire M951 light or, if you’re looking to mix it up a bit try this baby (photo below, but expensive, so hold onto your wallet!)

SUREFIRE M600 Ulta Scout Light (super bright)







Want to see more gun builds or submit one of your own? Shoot us a message on Instagram @rangefindernow or email us rangefindernow(at)gmail.com

Also, peep these.


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