This is the Double Barrel AR15 as seen in the TFB articles M16Z and Pipe Hitter 37mm.

This was formerly released in a limited trial and hosted briefly on most file sharing sites.

It was gradually censored or removed from those sites, and it is here to stay on Defcad and Odysee.



To assemble this firearm you will need:

-Everything for the dual reciever available in this pack

-Assorted M5 bolts in long sizes, (up to 100mm in length) to assemble the lower

-Two AR15 FCGs (such as binary for hilarious results)

-One standard right handed AR15 upper reciever

-Stag Arms or similar left handed left ejecting upper reciever and bolt carrier

-Handguards totalling less than 45mm wide for each side *0

-3.5" long 1/4 hitch pins or bolts as take down pins

-PDQ or similar right side bolt catch/release (if bolt catches are desired) *1

-Left side magazine release (if separate ejection is desired) *2

-Fortis Clutch or other one sided charging handle *3

-An optic for one or both sides that clear the recievers *4

-Left and Right Side Safety Selectors and grips *5

Additional Requirements as marked with *:

-0: There are 45mm between the barrel centerlines as assembled. The handguards will collide if they are over 45mm wide. The original M16z features two milspec m16 handguards and one has been cut along with the delta ring to avoid collision.

-1: The bolt catch for the right side reciever will function but will not be accessible as it sits between the recievers. A bad lever or similar inside trigger guard solution is not advised.

-2: A left side ambidextrous magazine release can be installed on the left receiever. In the files provided an extended printable magazine catch button is included that is pressed when the magazine latch on the right receiver protrudes and hits it.

-3: The upper recievers are close enough that the charging handles would collide. I used a Fortis Clutch charging handle on the left side. You could also simply cut down a milspec model.

-4: Sights with large quick release levers or knobs, such as a detachable carry handle can not be placed on the right reciever without modification as they will collide with the left reciever

-5* A grip can be placed on the left and or right receiver. The files include one extended safety bar that works for both sides. Please print this in at least PLA+ or stronger and test for function. Two regular grips or one normal and one cut down grip can be used to retain separate safeties.

Additional Information:

-If both recievers are properly faced and both barrels are the same make and model the points of impact will remain relatively parallel when used with the free floating tripod lug that attaches to the lower reciever. I have not made any device that adjusts the barrels nor fastens the handguards to eachother.

-The fiream can be assembled with only a left or right grip and the long paddle on the far side trigger, or two grips, preferrably with the opposite side trimmed down and two short paddles for pulling the opposite side trigger.

-Light profile barrels and furniture are reccomended for keeping the overall weight of the platform low. I used milspec barrels and handguards that are not free floated because the entire upper recievers are free floated from the tripod and the milspec handguard mitigates heat well.

-Drum magazines will not clear the reciever but two surefire 60 or 100rd magazines will fit simaltaneously, as well as ATI polymer 60 rounders with mild collision.