Making the decision to start creating your own guns is pretty big. It is a very satisfying pursuit and you end up with a gun that you can truly say you made. It is customisation taken to the limit.
In most cases, customisation means selecting the parts that you want fitted to your AR, ordering them from a reputable dealer, and fitting them when they arrive at your door. In some cases, you might need a special tool to be able to fit them, but such is the power of the AR design, that many simply slot into place. However, some parts a significantly more complex, and top of the list is the 80% lower receiver. So, called because it is effectively a blank that has only been 80% completed, you, as the user, gets to finish off the remaining 20% in the way that suits your particular build. The 80% Lower really is hands-on gun building.
The 80% lower is available from many sources so getting one isn’t difficult. But actually completing an 80% lower with any degree of accuracy is a bit trickier. In fact, if you tried to mark out the locations of the holes and slots that you need to introduce by hand, you are highly unlikely to get them in the right place, and that could mean that your new lower is actually scrap. If you want to introduce these essential features to your 80% lower, you are going to need the accuracy of a jig and drill press.
Luckily, there are plenty of jigs on the market, and they are usually of good enough quality to ensure that you get your holes and slots in the right place, and that your AR works as intended. Make sure that you pay for a quality item as it will last, and you will want to use this again and again.
So, you have your 80% lower, and you have your jig. The last essential part of the equation for getting everything right is a good drill press. While a jig will go a long way to getting your holes and slots in the right place, but there is still the potential for the features to go in slightly skewed, and that is going to ruin your lower before you get a chance to use it.
A drill press is essentially a powerful drill that is sufficiently rigid to ensure that when the drill or milling tip is used, it won’t deviate from the path and your resulting holes and slots will be perpendicular to the face that they are being placed in. Get these wrong, and at best, your AR will work badly, at worst it won’t work at all..! Therefore, a good drill press is going to be your best friend when it comes to getting hole positions right.
Key to the drill press’ function is the fact that it is a pillar drill that is enormously rigid, so even small bits won’t be forced off their path. And a drill press is designed for milling operations too. A drill press has its high-quality chuck mounted via a tapered arbor that connects the chuck to the quill and allows the system to take large side loads with ease, so a drill press is just as comfortable being used with milling tools – which exert a sideways force on the tool – so you can place slots as required just as easily as holes.
Building AR’s can become addictive, and you will find that you don’t want to stop at one. In that case, you are going to want great tools that will stand the test of time, so invest in a good jig and drill press.