How to fix: G3 Barrel Wobble

Discussion in 'Gun Building, Modifications & Repairs' started by germanphoenix13, Dec 5, 2012.

  1. germanphoenix13

    germanphoenix13 Member

    OK so as many of you G3 owners out the know, G3's have terrible barrel wobble. Looking at some older products, i found a G3 'Backbone Kit' by a company known as Radish. Now I didn't find very much info on it, I decided to build one of my own, based off of that one picture I could find. and here we go:

    Thing you are going to need:
    about a foot of .625 "diameter rod or pipe(1/2" CPVC, 1/2" copper pipe, etc. I used Nylon rod I bought from McMaster for a project a long time ago[RPMBNB])

    some type of rotary cutting tool. I used a dremel and a lathe(because I could) rotary tube cutters work just fine, and if you have a steady hand, the dremel does it all.​

    Let's get started!
    First you need to disassemble. I'm only doing basic pictures, so I'll just assume you know how. once done, cut off the main pushing rod on the G3's cocking bolt. once that's done, carefully tap in your .625" material down to the end. It should be a pretty snug fit.

    Once that's done, open up your upper receiver and remove all the stuff associated with the cocking assembly, as toss it all except for the fake bolt. What you need to do is cut that in half, and use your dremel or other rotary tool to shave down the inside flush to the inside of the the front section of the fake bolt. you need to do this so you can open and close your bolt.

    The last thing you need to do is to carefully cut the end of your material so the back end sits nicely against the back plate of the part that held the cocking assemble spring guide in place. once that's done, cut a slot into the bottom of the material to make room for the spine of the gearbox. Once done, just reassemble the upper receiver and slide your barrel assembly back on and reassemble as normal.

    Because the cocking tube has lips that go around the the body, the .625" material pushes against it, making a snug fit. If you have a claw mount on it, the even more so increases the stability by crushing the plastic body against the material further back, giving it more support This literally gives your G3 a backbone, and significantly reduces barrel wobble at the cost of the all favorite HK slap.

    You can use pretty much any .625" diameter material, but the stiffer the better. I used white nylon because it's what I had at the shop.

    So what do you guys think, good guide? I hope this helps alot of G3 users with plastic bodies out there.
  2. Ehudakineyah

    Ehudakineyah New Member

    Good guide :) deserves a sticky

    And maybe more pics?