Machining the EP80 platforms


How to ensure a properly functioning build for yourself

EP80 lowers must have the fire control group machined to E P Armory specifications. Our adaptable jig system is designed to remove only the needed material for the fire control group while leaving a rear wall between the rear lug. Removing the rear wall will inherently void any warranty and make the EP80 weak causing a buffer tower break possibly imminent.

100% Lifetime Warranty against manufacturers defects. Please read warranty information for pertinent information. By ordering you agree to the warranty program. Product Description:     Strengthened rear buffer tower with tapered threads to ensure a tight fit and structural integrity for larger calibers on the market.     Unmarked pin guides     Precision drilled Pivot and take down pins     Kevlar reinforcement like no other     Flared magwell     Oversized pivot pin housing     Oversized Buffer tube neck     Safe/Fire marking on receiver     Integrated trigger guard for easier use     Rear lug area already completed     Made in the U.S.A.     Limited Lifetime Warranty     Chemical and corrosion resistant     Lightweight design. Pistol grip hole unthreaded and undersized 50 thousandths so the 1/4x20 LPK screw will cut very tight threads for a firm fit.

Getting ready....

#1 Gather all safety equipment for the builder and tools needed for the machining process.

#2 Unpackage the EP80 precursor.

#3 Attach the E P Armory adaptable jig to the EP80 receiver.

#4 Attach the EP80 receiver and jig firmly into a vice so it will not move during machining to the receiver.

#5 Set your desired machining tool to a speed setting desired (recommended 1500rpm) and apply cooling air either positive or suction whichever is desired. Do not use cutting oil it will make a mess and make the cutting area less visible.

#6 Drill the fire control pin holes and safety hole before the actual fire control pocket using the tool kit from E P Armory. 5/32 hammer and trigger pin, 3/8 for the safety hole. Drill one side and then the other. Do not drill straight through.

#7 Using the 5/16 flat end mill bit you can begin the FCG pocket. Take small amounts less than a 1/4" at a time to keep chatter down and tooling as cool as possible.

#8 Once the FCG and side holes are completed begin assembly of the build

Installing the buffer tube to the buffer tower by threading.

When installing the buffer tube to the buffer tower you have to ensure the tube is properly aligned to the tower. Apply a light amount of lubrication as the threads are tapered. You will feel the amount of force needed to feed the tube into the tower increase after 1-2 threads. Ensure the prop alignment and continue threading. (If you cross thread or feel it turn improperly remove the tube and apply more lubrication.

Tapering the threads has made E P Armory the only polymer/kevlar blended lower able to handle the larger calibers on the market such as 7.62x39/450Bushmaster/458Socom/50Beowolf.

Once the lower has been completely assembled and a upper receiver caliber has been designated make sure your buffer spring and buffer are the proper weight for the caliber to be used. All buffers are not equal nor the same weight. ( You cannot put a H1 buffer into a 458Socom build on a EP80 and expect it to last). Buffers and springs are like shocks on a vehicle, you just can't use a honda accord strut on a Ford 350 and expect a good ride.

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