AR15 upper vise block

thingiverse

I modeled this generally off of the Geissele Reaction Rod but modified for 3DP. This is designed to hold your AR15 upper receiver in a vise so you can work on it or assemble it. I recommend printing this at a high infill to support the weight of the upper and resist crushing by the vice. Also you will need to use a raft to prevent warpage. This fits diagonally in a Ender print bed. This is strong enough for basic assembly of the rifle but will twist if you try to use it to torque the barrel nut. Do not use when tightening the barrel to final torque, the vise will break.