Dirty Bird AR-15 ASAL Free Float Quad Rail

The Dirty Bird Free Float Quad Rail is a no-nonsense American Made rail system designed for versatility and simplicity. It features a monolithic top rail and is precision machined from 6061-T6 aluminum extrusions. Next, it is type 3 hard coat anodized, so you can be sure that this handguard can withstand an incredible amount of abuse. Front and Rear Sling Swivel Attachment Points are integrated into both the left and right side rails and are designed to limit the swivel’s rotation preventing twists and tangles in slings. The handguard is fully dehorned and deburred. It is a true do-anything rail system and the cost-value ratio makes it very hard to pass-up.

• Available in a 9.35″ and 12″ length.
• 6061-T6 Aluminium
• Type 3 Hard Coat Anodizing
• 1018 Steel Barrel Nut
• ASAL Attachment System

ASAL Attachment System Report

Eliminating Handguard Slip

The shockwave generated when firing an AR-15 creates over 1000 G’s of acceleration. This means that a one pound part will generate over 1000 pounds of force every time the rifle is fired. Combined with the thermal cycling generated when firing multiple rounds, it can be very difficult to keep a handguard from slipping forward or rotating. Many attempts have been made to solve this problem. Some solutions are overly complex, resulting in difficult installation and high manufacturing cost. Some designs, like the popular key seat, are overly simple. The key seat will stop a handguard from coming completely off of the rifle; however, it still allows some forward slip and 360 degrees of rotation.

Handguard Lift

Free-floating handguard mounting systems tend to produce an upward lift of the handguard, resulting in the muzzle end of the handguard floating higher than the receiver end. This lift can adversely affect the performance of the rifle, especially when using iron sights. Even if the handguard is only used for protecting your hand, a small amount of lift is noticeable when aiming down the sightline. This visually makes the rifle seem crooked. Even if the rifle performs with precision, it can create an optical illusion, thereby reducing accuracy.

Solution

The patent pending ASAL^TM (Anti-Slip / Anti-Lift) system is simple, easy to install, easy to manufacture, and a cost effective solution to handguard slip and lift issues. The ASAL^TM system locks the handguard to the barrel nut using a CamLok^TM fastener featuring a 10 degree taper angle. This small taper creates a huge mechanical advantage, greatly increasing the force generated by a standard screw. The mating groove in the barrel nut is offset so as it is tightened, the handguard is pressed against the upper. This mitigates lift while also preventing slipping or rotation around the barrel’s axis. The result is a handguard that will not slip, rotate, or lift.

The result is a 10x decreases of handguard muzzle end lift.

Made in the USA

Dirty Bird Industries’ Limited Lifetime Warranty

Available Colors

Black, Magpul™ FDE, Magpul™ OD Green, Midnight Bronze, Sniper Grey

Weight	N/A
Length	9.35", 12"
Color	Black, FDE, Midnight Bronze, OD Green, Sniper Grey
Weight	22.1oz