80% lower difficulty level for 1st timer?

ARqueen15

New member
Hello...how hard is it to assemble an 80% lower?

I've had ar's, ak's, and many other platforms for some years and enjoyed all of them but I've wondered about building one myself to make it exactly to my liking.

I'm a female with zero experience with milling or machining in general. I have watched the videos created by the various 80% lower sellers (usually with their jigs, drill bits, etc). Simply watching them makes it seem doable but of course there's an element of precision and manual dexterity that no video can convey.

I also read about enough failures to think it's not a total gimme that anyone can do it perhaps it's a question of the quality of the lowers.

Normally with an off the shelf ar, I'd look for a forged lower but imagine such a material is harder than say polymer while being much more robust.

So any that ought on how realistic this is for a first timer?

I'm well aware of aware stripped lowers, rifle kits, etc but my interest, given the current political climate and what's on the horizon, (perhaps you disagree but it looks iffy to me) is strictly in the feasibility of the 80% approach.

I won't list the companies I've looked at since that might violate the tos for the forum but I'm familiar with all the common ones and the jigs, kits, lowers, etc that they offer.

Any suggestions would be appreciated.
 
Last edited:
The 80% lower has to be machined before any parts can be assembled into it.
If you have a mill and know how to use it you will find it easy. If you don't have a mill or have no experience then it will be less easy and possibly an act of futility. There are a number of guides to simplify the machining process and even one that utilizes a router with a special bit that gives a great finish. The tools and guides double the cost of a stripped lower and can triple the cost of the 80% lower.
The only reason I can see for building from the 80% lower is to have a gun that has no history or serial number. It's perfectly legal in some states, in others you can run afoul of the law.
 
I'm a female with zero experience with milling or machining in general.
Being a female has nothing to do with it.
On the other hand, if there was a time the old adage applies, this would be one of those times.
"If you have to ask, don't."
Please don't add to all the home made butchered crap that's already out there.
Enjoy the ones you have made by folks who know how.
 
Last edited:
What equipment do you own, and what is your level of experience with it?

Anyone (man OR woman) that's rarely held even a tape measure, hammer or level- much less run a mill or even a drill press at all- would be in over their head IMO.
 
^^^
I would have to agree.
Back in the early 70's, I and one of my buddys made one complete from a reject casting using a heavy drill press and a handful of files. We did have a print.
 
no history or serial number. It's perfectly legal in some states, in others you can run afoul of the law.

If I remember correctly, the ATF frowns on firearms of recent manufacturer that have no serial number.
 
If I remember correctly, the ATF frowns on firearms of recent manufacturer that have no serial number.

Source? It's perfectly legal (on the Federal level) to manufacture a firearm with no serial# for your own use. There may be state or local laws against it, however.

As for the OP's questions, it's not terribly difficult with the proper tools. I have a decent drill press, and am looking at a milling drill press vise which should make the process vastly easier. http://www.sears.com/s-e-g-milling-drill-press-vise-portable-equipment-at/p-SPM8746460726?plpSellerId=S.E.G&prdNo=1&blockNo=1&blockType=G1

HOWEVER, as a practical matter, you'll be far better off to find a lower with a SN#. If you buy one as a private sale, there'll be no record of the transaction if that's what's worrying you. You'll wind up spending ~$200 for a drill press, ~$85 for the milling vise, ~$85 for the jig, and ~$50 for the 80% lower. It would really only pay you to get this setup if you were going to machine and sell lowers, but you can't without a firearms manufacturing license. :eek:
 
Is it legal to put a serial number on? I saw some 80% (Probably closer to 60%) flats that were being sold through FFL paper work because they were serialized when they were stamped on the dies.
 
If you are making a gun for your own use and not resale, it does not need a serial number. If you might sell it in the future, you can put any number on it along with your name and address either now or at the time of sale.

The reason I usually see given for use of an 80% receiver is that they are for making up special guns for custom work. Maybe, but most folks who do it seem not to talk about custom work, but rather to brag about having a legal but "untraceable" gun. (Of course, if BATFE really were listening in on every private conversation about guns, they would already know who had them - and no time for anything else!) I would say go ahead and have fun but my limited experience is that most of those 80% receivers end up ruined and in the junk box.

My suggestion is to simply buy a complete (and numbered) receiver or, given your skill level, simply buy a complete rifle.

Jim
 
Many thanks for the replies and especially for not sugar coating the answers (re... over my head, "if you have to ask. ...")

So to add detail based on your comments. ..

1.... no experience with a drill press or a jig though I certainly know what they are and what they do.

2... ive used tape measures and done small, (small! ) around the house sort of things, can change the oil and a tire on a car, and do calculus... but those videos don't exactly reference derivatives and integrals :) :)

3... I'd thrilled to get an off the books lower in a ftf setting but I wouldn't even know how to find one and the few places I've looked like various equipment exchanges on forums all inevitably involve sellers wanting to go the ffl route which sort of defeats the purpose.

4... ive no legal concerns and even have a ccw so this is more a case of building for a rainy day which I happen to think is sooner than later.

5.... its perfectly legal to build an 80% in my area as I'm in a"free"state and this would be 100% for personal use... that's really my entire point and I'd never even consider selling it besides it being illegal.

Again thanks for the advice and being patient with a neophyte to these 80% lowers and machining in general.
 
With minimal mechanical or tool experience, I'd say you're better off avoiding the subject.

...But so was I when I finished my first one (though I did have substantial mechanical and tool experience).

If you really want to do it, just for the 'exercise', I'd say buy two or three to practice on (assuming polymer w/ jig). If you get one that works, that's great. But, plan on buying two to three more in order to get a "good" one that works, functions without 'special needs', and doesn't look like crap.

I've finished two polymer "80%" lowers. Even though I did everything right and had some decent tools for the job, I ran into major issues with the material itself wanting to chip and break out. Total fluster cluck, and it ruined me for any kind of polymer 80%.
One was fully functional, but crap. The other looked fine and ran fine, but still wasn't "right". One now lives on the wall of shame, while the other lives in the parts box as an exemplar for AR magazine well dimensions (for use in converting .223 Rem bolt action rifles to use AR mags).


If you're looking at aluminum "80%" lowers, don't even bother.
You need access to real tools, or a hell of a lot of time with hand tools and a drill press, to get that done reasonably well. (Not even properly, just reasonably well.)
 
ARqueen,
If you're undaunted, look for adult education classes in your area.
There might be some on acquiring the kinds of skills necessary to pursue your ambition.
That's where I learned welding.
 
Learning how to use a milling machine takes time. You may want to find a machine shop class at some junior college. Second, you can take the short cut route and buy a jig with which you can drill out the lower. Much less skill required for that. Good luck.
 
Depends on your machining knowledge, equipment on hand, and the biggest obstacle is, are you all thumbs????? as some folks are.
 
If you invest in an easy jig with the proper tool kit and trim router it makes it an easy task to complete an 80% lower and have it look and function properly. The jig, tool kit and router will set you back about $300. Just be patient, follow the instructions step by step and All should turn out well.
 
ARQueen,
If you are willing to make the attempt you will likely do fine. Guys get their egos all involved and rarely read the directions or even follow well meant advice. If you are careful and can follow the directions that come with the jigs I would advise you to go for it. You know math so details are easily approached. Do it! :)
 
I appreciate the warnings, cautions, and encouragement!

I think I'll go ahead and order a 2 or 3 pack of polymer lowesr plus a jig from one of the companies that specialize in these ar builds. I don't want to break any forum rules so I won't list any manufacturers... with that said do any of you have any suggestions on who to buy from?

If it's not appropriate to discuss companies or make specific recommendations in public then I'm open to a pm.

Cheers
 
Back
Top