Apex Handguard Installation Instructions
Revised 3/14/13
INSTALLATION VIDEO-CLICK HERE
Apex Handguards are designed to be rigid and strong, to hold accessories stable, and to create a secure connection between firearm and shooter. Installation requires some knowledge of the assembly of AR10 & A15 rifles. You may choose a qualified gunsmith to install your handguard, if desired.
Materials required: Factory Barrel Nut Tools Required: 5/32'' hex key
Blue Loctite (DO NOT USE RED OR GREEN) 1/8'' hex key
DISCLAIMER:
Tightening screws during installation will mark the finish on our products. If product is returned within 30 days of purchase date:
Never installed 100% refund
Previously installed 50% refund
All returns are evaluated before refunds are made.
Accessory and Top Rail Installation to Handguard:
Accessory rails install more easily before the handguard has been installed on a rifle.
Accessory Rails: Place the rail nuts at the desired location inside the tube and insert screws thru the rail and tube to the nuts, adjust to position and tighten. The rail nut is designed to deform slightly when drawn against the inside of the tube, thus securing the rail from loosening inadvertently; however, Blue Loctite may be used as a further precaution.
Top rails must be installed AFTER the handguard has been installed on rifle.
Top Rail: Use included special flat head screws to attach rail directly to the tube using the appropriate holes in the top of the tube. A 1/16'' hex key is provided with every top rail.
Handguard Installation to Rifle:
MAKE SURE WEAPON IS UNLOADED BEFORE INSTALLING HANDGUARD ON RIFLE.
A factory barrel nut will be required to be installed and properly torqued according to rifle manufacturer’s specifications (generally between 30-80 foot pounds), if assembling a rifle from the ground up.
If retrofitting an existing upper assembly, remove existing handguard and delta ring leaving the factory style barrel nut in place.
If using a low profile gas block, whether covered by the tube or exposed, the gas block can be installed at this point.
If using a front sight gas block, it must be secured in place after the handguard is installed.
Place the two halves of the Apex Handguard System clamp around the barrel nut and thread the four included socket head cap screws partly in, leaving loose enough to allow some movement in the clamp.
Slide the end of the handguard tube with the four holes over the clamp and loosely install the four included button head screws. (If permanently installed muzzle device prevents the tube sliding on from the muzzle end of the barrel, it can be placed from the rear before the clamp is installed.) The holes will only align in one position, assuring proper positioning.
Once the tube is over the clamp, position the assembly so that the clamp screws are facing the bottom of the rifle and snug all screws evenly, maintaining an equal gap between clamp halves. Lastly, tighten all screws evenly to prevent movement of clamp.
If a front sight gas block is used, it can now be secured in place. Extended Apex Handguard System models require removal of the original sling swivel. Additionally, the ears of the swivel will require trimming. An access for pinning the front sight gas block to the barrel is provided by a hole in the side of the handguard tube.
After final safety and function checks, it is recommended that one screw at a time be removed and secured with Blue Loctite or equivalent, and torqued to approximately 60 inch pounds. As with any piece of equipment, the screws should be checked periodically for tightness.
The most common problem occurs when clamp screws are over-torqued. Torque is determined by multiplying the applied force by the distance from the pivot point to the point where the force is applied. A standard 5/32'' Allen wrench is approximately 4.0'' long; therefore, it will require 15.0 lbs. of down force to equal approximately 60 inch pounds.
