Machining an AR15 lower receiver

[Highpower]

(06-29-2012, 08:38 PM)DaveH Wrote: Ah well, one does have to admire his spirit.

Indeed Dave! A+ for effort!

I bet Bob (krv3000) with just a file and a hacksaw could do it

DaveH

I do believe you are right about that too Dave. But Bob has the experience behind him to make it work and it shows. This poor guy on the other hand knew nothing about machine work and wanted to give it a try because he saw others doing it. Had he gotten some better advice in the beginning it could have been much more enjoyable for him instead of frustrating.

Willie

[ScrapMetal]

(06-29-2012, 08:31 PM)Highpower Wrote: This is the kind of thing that makes me sad though. Bad internet advice. This poor guy was convinced by someone else on another forum that he could successfully do this kind of work with nothing more than a bench top drill press and a Dremel tool.

I really want to see a "build thread" from the guy who suggested that. What a train wreck! I wonder how he did the mag well or if he had someone else do it? In that pic it looks pretty decently done.

Now, I'm sure there are guys that are capable of managing that with minimal to no tooling but they are few and far between (Yeah, Bob does come to mind for some reason. ) and really have to know what they are doing.

-Ron

[Highpower]

Ron, what he has there is known as an "80%" receiver, which means that the factory has already completed 80% of the machining needed to be done in-house. The only portion left needing machine work is in the center of the forging. As long as the total work done is <=80% they can sell these forgings as paperweights since they cannot "readily" be converted into a completed receiver. A 81% completed forging would be considered a "firearm" and subject to all the rules, regulations, and paperwork required the same as if you were buying a factory rifle off the rack.

There are places that sell special jig set-ups to those interested in completing that last 20% of the work on their own if they are so inclined to do.
http://www.cncguns.com/tooling.html

They are geared more toward folks that may have a small home shop but don't own an industrial sized mill. A lot of guys who are still a bit nervous about using their new mill-drill will buy these jigs to help guide them, and are very successful.

Somebody told this poor guy those jigs were nothing but a waste of money, and he could do the work by hand just as easily. I'm guessing his name wasn't Bob.

[ScrapMetal]

That makes sense on the 80% receivers (silly gun laws ) and it makes it more tragic as he spent even more on it.

Thinking about it though, I'm going to lay a good part of the blame with the guy who took the advice and tried to use the drill press. The man definitely does not have any understanding of his tools, their capabilities, or their limitations. The guy who gave the advice still deserves a swift kick to the groin.

Remember kids, don't believe everything you see or read on the internet!

-Ron

[Highpower]

Somewhere I once read that "Ignorance can be cured with education, but stupid is forever...."

I think we have a case for each in that particular situation.

"A good man always knows his limitations." ~ Harry Callahan

[doubleboost]

First class work
Willie
Thanks for posting all the pictures
I think i will have a play with my air rifle now
John

[Highpower]

John, didn't you make some new parts for refurbishing your air rifle awhile ago? I don't suppose you happen to have pictures of that do you?
(Wink, wink..... nudge, nudge....)

Willie

[doubleboost]

Hi
Willie
I think i have
Will have a good look later
John

[NevadaBlue]

Willie, that is just outstanding work. And for me, the pictures are golden... I learn a LOT about setups from looking at actual work being done and your pictures are as outstanding as your work. Thank you for posting them.

Beautiful gun!

Ken

[Highpower]

Thanks Ken. Luckily I found Ray Brandes' write up on machining these after I located the first set of drawings. That definitely helped more than anything. Having purchased several of his products in the past I knew I couldn't go wrong. His work is incredible.

The next build will be even more challenging for me. I used a factory CMMG upper for this one. For the next one I want to make use of a Colt conversion unit that I have. I'll be starting off with a 1" barrel blank that I want to be a bull-barreled dedicated .22 rimfire rifle. I'll have to remove the chamber adapter from conversion unit because there won't be a .223 chamber to insert it into.

The fun will be in figuring out how to attach the conversion unit directly to the barrel and then chamber it in .22LR. So it's definitely going to be a Frankenstein project. We'll see how it goes.....



Willie