A few Good Sets of 80% Lower Build Instructions

[turbo89]

I just stumbled on this writeup doing while browsing the internet, and figured I'd pass it along:

With a Drill Press:
http://www.colfaxtactical.com/Docs/Justins%20solid%20tutorial.pdf

With a MIlling Machine:
http://www.colfaxtactical.com/Docs/Fire%20Control%20Pocket%20with%20a%20DRO.pdf

Source:
http://www.colfaxtactical.com/Instructions.html

Disclaimer: I didn't write these instructions, thus I take no credit, and cannot confirm the accuracy of the instructions provided.

 

[KH56010]

All those instructions are good, Colfax actualy makes the best 80's in the market since they already mill out the rear shelf. Guys like me on a minimill will have a hell of a time trying to mill out that shelf on a different 80 lower because of the buffer tube support.

No matter what you do when milling out one of these, whether you punch a little deep or screw up a little and take too much off the sides. Don't worry about any of that, the gun will work it just won't look pretty. However, get the trigger pins and safety hole dead on. Either with a Jig or measuring and using a quality punch. Everything on the lower can be +/- a huge amount except for those holes. Messing them up will throw the angle of the hammer off and will cause it to not fit into the bolt carrier to strike the primer. Nothing will go wrong (no parts flying out like with a botched reload/squib) but nothing will go boom either.