THE AR15 LOWER

Building your own:

Just what does building your own mean? It boils down to finishing (home machining) your lower receiver and then assembling the remainder of your AR15 kit. In another words, attaching everything necessary to the lower in order to complete your AR.

So why on earth would you want to construct your own AR15? There can be a lot of reasons. First, it's fun! Secondly, you can save a lot of money by constructing your own. Or there is also a bunch of you that love a challenge. Maybe you are into total customization. Perhaps you seek the sense of accomplishment in knowing that you are out there on the firing range using the actual beauty that you built in your garage. Your buddies probably will not believe it!


Even the BATF says that we can build our own for our personal use as long as it is not built for the purpose of selling or giving it to someone else. But... you have to be able to legally own a firearm. From everything else that we understand, the BATF does not require it to be registered either. Since we are not lawyers, you will need to do your own legal research to determine what the laws are in your local area. We can, however state, that if you live in California, your AR15 has to be California compliant in order to be legal.

At the bottom of this page is a link to our downloadable instructions.

We start with a raw 7075 heat treated forged lower and precision CNC machine it to military specifications. This is exactly the same forging that many of the major AR15 manufactures use.

 

Please do not mistake these for castings.  They are not.  They are forgings and there is a big difference between castings and forgings. In a nut shell, a casting is when aluminum is melted to the point that it can be poured into a sand mold. It is then allowed to cool and then removed from the sand. A forging is when aluminum is heated to the point of being very malleable, but not liquid.  It is forced, under pressure, into a steel mold, allowed to cool, and then removed. A forging is superior to a casting.  It retains all of it’s strength properties after forging.  If you start with 7075 alloy, it stays 7075 after forging.  Castings, on the other hand, loose their strength properties. A forging can be anodized whereas a casting can not be anodized.  A casting has to be painted.

 

Raw forging

indexpic    

 

 

Then we finish about 80% of the necessary machining.

   

 

Our magazine wells are beautifully broached, insuring perfect corners.



More Details

Our 80% lowers are available "in the white" or black mil spec hard anodized.

 


What is complete and what needs to be completed:

 


Already completed:

1) Magazine well
2) Pistol grip area completed 
3) Trigger guard holes drilled
4) Front and rear pivot pin holes drilled and reamed
5) Selector retainer hole drilled
6) Main hole for buffer tube drilled and threaded
7) Buffer retainer hole drilled
8) Magazine release/catch slots finished
10) Take down lug milled out (you may need to slightly open it)

 

To be done by you:

A) Fire control pocket
B) Drill trigger pin hole
C) Drill hammer pin hole
D) Cut trigger slot
9) Selector hole


What you will need:

At a minimum, a floor type drill press will be necessary. You will want to insure that the chuck runs true. While you can complete it with a drill press, a mill-drill, mini mill, or an actual mill will make your job much easier. Other than your machine (with a vise), you will need some common tools such as a set of drill bits and some simple calipers.

You will also probably want a machining/drilling jig (a fixture). The jig is to help hold the lower in a vise, without damaging the surface, while working on it. If you plan to only build one AR, you can sell the jig on any one of the many AR15 web sites after completing your lower. They sell quick and often times you can recover 75%-85% of what you paid for them. There are those of you that may want to go in with a couple of friends and split the cost of the jig. We recomend that if you are using our lower, then use our jig. On the other hand, if you are using another companies lower, use their jig.


Download Instructions

Finding answers to your questions along the way can be a hassle. We want to make it easier. We have taken months of research and condensed it into this download. Although we are not able to offer personal technical advise in terms of your machining, we do offer numerous links to sites and forums where you can find the answers. In addition, two tutorials covering how to complete your lower as an 80% are included. We provide links (in the AR-15 Intro) to the important and relevant sites where just about any question can be answered. These are sites that you will probably want to stay with long after you complete your first AR15. There is really no limit in terms of the knowledge and expertise available.

Intro into the AR15

Actual Tutorials (the nuts and bolt of "how to");

Machining with a DRO

Building an 80% Lower by Justin Halford


Manuals:
AR15 manual (US Army M16A2 manual)

Drawings:
PDF format

 

A note about the ATF "Letter of Determaination"

The letter is what manufactures obtain from the BATF that states their product is "not a firearm". We indeed have ours. Contray to a lot of internet forums, an ATF letter of determination does the end user no good. It only keeps the manufacturer out of hot water. Since you, the builder, can build an 80% lower into a 100% lower, the letter does you no good.

Click on the link below for the jig instructions in PDF format.

Instructions

 

 

 

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