Hello! Thanks for checking out this absolute monstrosity of a carry handle that I have designed and shared with the world! 

IF YOU HAVE LITTLE OR NO EXPIRIENCE IN PRINTING BIG PROJECTS TURN BACK NOW PLEASE!

This carry handle was brought ot me in a 3AM stupor while I was on vacation and rapidly came to fruition over the past months. 
It is designed to fit an AR15 (or really any rifle for that matter) with a monolithic top rail. I cannont gaurentee fitment for all rail manufacturers but they should be close enough. 

Included in this pack are the following components;

x1 Front mount and its associated rail retainer
x1 Rear mount and it associated rail retainer
x1 Aimpoint footprint mount; This was specifically desinged around the use of the SIG Romeo MSR red dot but may work for other similar sized optics
x1 Rails mount; This should fit a variety of small red dots and holographic sights, as long as they fit the 64.5mm rail segment (future inserts will be developed to accomidate larger red dots) 
x1 6.5" mid-section; The middle segments are measured from the rear face of the rear mount to the front face of the front mount. 
x1 7.5" mid section; This is the longest middle segment and may not fit a 250mm print space vertically if your z off-set is too far off ( I may have to rework this one eventually)
x1 13" front and Rear segments; These segments ( and the 15" versions) dovetail into each other in the center for extra ridgidity using a set of bolts
x1 15" front and rear segments; see the 13" version 
 
The hardware you will need depends on the length of the handle you intend to assemble. The shoarter version require 2 less M5 screws and nuts. 

Assuming you intend on making the longest possible handle you will need the following;

x1 M4x25mm socket head screw
x2 M5x30mm socket head screws
x1 M5x25mm socket head screw
x4 M5x20mm button head screws
x7 M5 nuts
x1 M4 nut

Printing the components can be very time consuming and uses a lot of filament. I suggest a strong filament like PLA+ or higher to lower the chance of the parts breaking.
In my testing I have found that printing with a high wall count and high infill helps the parts retain maximum durability. 
The front and rear mount sections should be 100% infill, you can get away with 75% on the middle section if it the short versions but for the longer versions I really recommend 100% infill. 

I printed my testing handles in Overture PLA Pro, 100% infil, 8 walls, 210C, all components printed vertically and it has survived me beating the absolute shit out of it for the past few months.

I have attached images of suggsted print orientations for some of the key components. 
  
Keep a few files and drill bits on hand to clean up any holes or mating surfaces for best possible fitment. There may be some unavoidable gaps due to shrinkage and other minor settings.

With all of that out of the way, good luck, have fun, dm me on twitter @ProSpaceDog with questions or concerns, and show me what you are slapping this horrible idea onto when its done!