Don't know if there is a similar thread here anywhere, but I thought, with the impeding new laws that are possibly gonna impede our right to keep and bear arms, that a thread about finishing a lower would be a benefit to those who are thinking, but not sure if they can, build their own lower for an AR rifle or pistol.
Yes, it does take a bit of skill, but not a lot. A mill is an extremely valuable resource, but... not absolutely needed. Start with an 80% lower, drill and ream the holes for the FCG (trigger, hammer and selector), mill the pocket in three stages and viola! You now have a completed lower that you built yourself and as of the writing of this post, you can legally do it and not tell MOM about it.
You will obviously need some additional items, Lower build kit, upper assy, barrel, etc.. but those are starting to become more and more available as time goes on. The caveat is, if you don't do it now before 10/1, there is no certainty with the impending legislation (though it seems to still be evolving and getting better explained as we near the deadline),that you will be able to do so after that time, so... get to it! Build yer own!!
Drill/mill jigs make the process a heck of a lot simpler. The ones we build locate off the takedown and pivot pin holes in the 80 lower and have drill bushings installed to locate the three holes needed through the side of the receiver. They can be used to clamp the part in a vise, use a set of short parallels to allow clearance for your drill and reamer to clear through the holes when doing that op. Drill the holes a bit undersized and then ream them to the final diameter (you'll get a much more precise and cleaner hole).
Now flip that sucker upright in the vise, clamp it tight and now we are ready to cut some pockets out.. The drill jig will typically allow you to bolt a plate on top of the receiver, or multiples to perform the three step milling for the pocket. Our jig uses a master plate that bolts to the sideplates and then has interchangeable inserts that bolt into it to allow you to trace the outline of the initial milling area and step down until you have the proper depth cut. Swap out that plate, chuck up an longer LOC endmil and now trace out the cut for the deeper section of the pocket until you reach the final depth of cut. Be careful to not go too deep, as you will be close to the bottom of the receiver and you need some meat there (but it ain't gonna be much.. lol). Now, insert the final guide, swap over to a smaller endmill and make the final cut to break the cutout for the trigger through the bottom of the pocket...
At this point I would take the lower over to the bead blaster and give it a good once over to blend in any machining marks and also to rough up the outer surface so that when plated, it will have a matte finish. If you take it to someone that is going to finish it for you, they should be able to do this for you as well.
Okay.. you don't have a mill.. no shop, just an old drill press and a dremel tool.. Well, I've seen a thread on here about that and it worked, though it looked painful!! LMAO If you have access to a drill press, you are almost there. A few tools and you can make it work! You are going to need a decent set of drills, a couple reamers and a few endmills to complete the job.. oh and a decent vise to hold the part. Basically instead of step milliing it on a Bridgeport, you can drill away (set a depth stop to prevent drilling too deep on each op) with various sized drills to remove as much meat as you can, then use the appropriate endmill to clean up the leftovers.
A cross-slide vise is an indispensable tool for this as well, but again, I have seen creative individuals do this freehand on a drill press by clamping a guide on the table to help keep the movement straight along the X axis and then moving it as needed to help guide the part along as you trace the outline of the pocket using the jig.
The most critical part of the build is the location and size of the three holes through the sides of the receiver. Some drill them first, some do the milling to remove a mass of material and then drill the holes. I prefer the latter, as there is less chance of the drill walking if you are just punching through a thin sidewall on each side. The pocket is not all that super critical, as long as it allows free movement of the parts inside and proper mating of the upper and lower, it'll likely work just fine!
You can do it.. it ain't rocket science, you just need a few tools and you can, in fact, build your own AR lower. NO WAIT, NO PAPERWORK and only you know you built it.. unless you post it here on the thread somewhere...
I need to get some pics, I'll try to work on that tomorrow, though I will probably not be at the shop where I can show em setup on the mill (too much on the chore list this weekend to hang out in the shop). If anyone else has pics of their builds, please post em up here to help others see what it's really all about. I know there are several threads about builds, I'll try to find some and link em here as well.
Oh.. most importantly, do some research on the net. There are tons of resources out there to assist you. The bible for building a lower from a raw, 0% forging is the Ray-Vin Tutorial. This is an INVALUABLE tool for those that wanna cut their own. The raw forgings used to be dirt cheap, less than $20, but.. there is a lot of work to get the hunk of forged alloy to a final, working part. Be smart and get a lower that is finished as far as the law will allow and still not be considered a 'receiver' and finish it up from there. There are partials out there (ours are complete except for the FCG machining) that have all the work done.. all the minutia holes completed, etc.. all you have to do is the FCG work and you have a working receiver!
The Ray-Vin Tutorial (it is several chapters and addendum's, save and print them all as a guide) -
http://arlower.ray-vin.com/ar15
Yes, it does take a bit of skill, but not a lot. A mill is an extremely valuable resource, but... not absolutely needed. Start with an 80% lower, drill and ream the holes for the FCG (trigger, hammer and selector), mill the pocket in three stages and viola! You now have a completed lower that you built yourself and as of the writing of this post, you can legally do it and not tell MOM about it.
You will obviously need some additional items, Lower build kit, upper assy, barrel, etc.. but those are starting to become more and more available as time goes on. The caveat is, if you don't do it now before 10/1, there is no certainty with the impending legislation (though it seems to still be evolving and getting better explained as we near the deadline),that you will be able to do so after that time, so... get to it! Build yer own!!
Drill/mill jigs make the process a heck of a lot simpler. The ones we build locate off the takedown and pivot pin holes in the 80 lower and have drill bushings installed to locate the three holes needed through the side of the receiver. They can be used to clamp the part in a vise, use a set of short parallels to allow clearance for your drill and reamer to clear through the holes when doing that op. Drill the holes a bit undersized and then ream them to the final diameter (you'll get a much more precise and cleaner hole).
Now flip that sucker upright in the vise, clamp it tight and now we are ready to cut some pockets out.. The drill jig will typically allow you to bolt a plate on top of the receiver, or multiples to perform the three step milling for the pocket. Our jig uses a master plate that bolts to the sideplates and then has interchangeable inserts that bolt into it to allow you to trace the outline of the initial milling area and step down until you have the proper depth cut. Swap out that plate, chuck up an longer LOC endmil and now trace out the cut for the deeper section of the pocket until you reach the final depth of cut. Be careful to not go too deep, as you will be close to the bottom of the receiver and you need some meat there (but it ain't gonna be much.. lol). Now, insert the final guide, swap over to a smaller endmill and make the final cut to break the cutout for the trigger through the bottom of the pocket...
At this point I would take the lower over to the bead blaster and give it a good once over to blend in any machining marks and also to rough up the outer surface so that when plated, it will have a matte finish. If you take it to someone that is going to finish it for you, they should be able to do this for you as well.
Okay.. you don't have a mill.. no shop, just an old drill press and a dremel tool.. Well, I've seen a thread on here about that and it worked, though it looked painful!! LMAO If you have access to a drill press, you are almost there. A few tools and you can make it work! You are going to need a decent set of drills, a couple reamers and a few endmills to complete the job.. oh and a decent vise to hold the part. Basically instead of step milliing it on a Bridgeport, you can drill away (set a depth stop to prevent drilling too deep on each op) with various sized drills to remove as much meat as you can, then use the appropriate endmill to clean up the leftovers.
A cross-slide vise is an indispensable tool for this as well, but again, I have seen creative individuals do this freehand on a drill press by clamping a guide on the table to help keep the movement straight along the X axis and then moving it as needed to help guide the part along as you trace the outline of the pocket using the jig.
The most critical part of the build is the location and size of the three holes through the sides of the receiver. Some drill them first, some do the milling to remove a mass of material and then drill the holes. I prefer the latter, as there is less chance of the drill walking if you are just punching through a thin sidewall on each side. The pocket is not all that super critical, as long as it allows free movement of the parts inside and proper mating of the upper and lower, it'll likely work just fine!
You can do it.. it ain't rocket science, you just need a few tools and you can, in fact, build your own AR lower. NO WAIT, NO PAPERWORK and only you know you built it.. unless you post it here on the thread somewhere...
I need to get some pics, I'll try to work on that tomorrow, though I will probably not be at the shop where I can show em setup on the mill (too much on the chore list this weekend to hang out in the shop). If anyone else has pics of their builds, please post em up here to help others see what it's really all about. I know there are several threads about builds, I'll try to find some and link em here as well.
Oh.. most importantly, do some research on the net. There are tons of resources out there to assist you. The bible for building a lower from a raw, 0% forging is the Ray-Vin Tutorial. This is an INVALUABLE tool for those that wanna cut their own. The raw forgings used to be dirt cheap, less than $20, but.. there is a lot of work to get the hunk of forged alloy to a final, working part. Be smart and get a lower that is finished as far as the law will allow and still not be considered a 'receiver' and finish it up from there. There are partials out there (ours are complete except for the FCG machining) that have all the work done.. all the minutia holes completed, etc.. all you have to do is the FCG work and you have a working receiver!
The Ray-Vin Tutorial (it is several chapters and addendum's, save and print them all as a guide) -
http://arlower.ray-vin.com/ar15
