Remix of an AR15 mil spec buffer tube clamp to use in a bench vise.

Mil Spec AR15 buffer tube vise block. 

Printed in PLA at 98% infill for strength so the buffer tube will not twist while tightening the castle nut.

The fit is very tight on the buffer tube, but the plastic seems to be plenty strong.

TinkerCAD link if you want to play with it:
https://www.tinkercad.com/things/bzVygMmsiSs?sharecode=9P9T9QyCE4OJQDBf-Qk66-hBN69XLxkYcHfhtC9Jh1g

I added a block at the bottom to use in a bench vise, and added a relief slit at the top.

I wanted to use this and two bench vises to keep the buffer tube straight while tightening the castle nut.