School me on 80% lowers

bobeano

Active member
Ok ive built a few AR-15 with stripped lowers. Ive never finished a 80% lower. I know need a jig,are they reusable? If they are reusable are there used ones aval?
I just got 2 80% lowers to add to the 2 reg stripped lowers i have. Guess i need to build something to go with the 223 and 6.8spc i have already built.
 
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a good jig makes it relatively easy, but those are also expensive. good luck getting your hands on a used one at the moment, unless you know someone with one.

when i did mine (last year) went to a friends and used his router jig.
that one was very reusable, and very user friendly. compatible with poly and aluminum. we were able to mill ar15, ar-9 and ar308's on it. they cut very nice lowers too.

takes just under an hour ish to complete a lower with the system he had. poly lowers maybe 35-45 mins (you can use a little deeper cut depth safely). he said it took him another hour+ to get it all assembled when he got it.

this is what he had, run off a dewalt variable speed router. so current market pricing you'll be $450-$500 to get setup this way, possibly more if you dont already have a bench vise.

https://www.5dtactical.com/products/the-router-jig-pro-multiplatform-ar-15-ar-9-ar-45-308-ar-10/




fwiw - this thing f*#$ing throws chips *EVERYWHERE* - even with the vac attachment going. seriously like 3+ feet. nature of the beast, you're milling aluminum, but making sure you know what you're getting into and all that. at the very least you're gonna want full eye and basic(or better) ear protection while using - if your space is comfortable enough, a full face shield would be extra nice.

i recommend making some kind of back stop to work in to keep the chips to a minimal area. even something as simple as a few pieces of cardboard setup in a V around your vise would work to help contain things.


the good thing is - with the market the way it is due to the upcoming rule change, these jigs are a real hot seller right now, so you could buy one and probably at the worst break even once the 80% regs hit here in the tail end of august. might even be able to make a few $ if demand gets super tight mid august for someone desperate.

good luck and have fun!
 
JMO, but why would I want to spend $450-500 on a jig and router to build an 80% when I can buy a 100% completely finish stripped lower for $65? And if you FUBAR it, you start over. Sorry, don't mean to be negative but makes no sense to me.

P.S. I'm not saying don't build one if that's your thing. I just think I'll stick to the ones that someone else did the hard work.
 
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i doubt anyone invests that kinda $ to build just one or two guns, its not practical. thankfully becuase it is so reusable, it does hold resale value. with the current political climate, one might even be able to use that system to mill a few lowers and even flip it for profit.

i was of the same mindset as you - just use complete stripped lowers - until i had a low cost option of getting to use my friends jig. why spend $35-90 on a 80%, and then buy a jig, and spend an hour + per to mill - when i can buy a poverty pony lower for $55.

and the chances of fubaring one with that system are... well.. almost nothing. if you can follow simple instructions, you can handle basic mechanical tasks and you're not a complete idiot anyway.
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the only thing we had that was close to an oops was someone tried to lift the router early (they hit the off switch and didnt let it come to a stop), and put a small gouge on the upper inside of the fire control pocket lifting it off the jig to re-adjust for the next cut. cosmetic only damage.

when my friend bought his jig (several years pre covid), the price was somewhere around $250 for the jig + router.

bunch of us milled on that jig before he sold the setup.

most of us threw him a few $ to say thanks for letting us use his toy. i built out several lowers so that my collection of uppers is now more complete firearms instead of having to play "swap the lower" quite so much.

so yea, just giving feedback on what i've used personally. and just how easy that setup was to utilize.
 
Its probably worth it if one was inclined to build more that one lower or like you said, had friends that also wanted to build. LOL, I don't even own an AR right now. I had a few in the past but seem to loose interest in them pretty quick. I just stick with the old fashioned bolt actions. LOL!!
 
so far i am keeping them in safe along with a cpl complete stripped lowers i have. i pick up 2 of each not knowing whats gonna go on with the way things are going. just looking for options at this point.
i do like the fact there is no paper work on them,jmo
 
Originally Posted By: crapshootThe only plus is a non-traceable firearm.

with the way things are looking to be heading - or at least the way the anti-gun crowd would like them to go - thats a potential big value added feature for sure.
 
Most people we see talking about how lower cost finished lowers have dimensional tolerance issues and lower quality which yields lower performance, folks running around banging the arfcom list drum, are the same fools which talk about how great their 80% lowers turned out, after using their inexperienced and poorly equipped hands to “mill” them.

If you want a lower with no traceability, buy via private sale. But frankly, even buying at a licensed FFL using cash and a concealed carry license in many states yields greater anonymity than does buying an 80% lower. Credit card purchases and online orders are far easier to track than 4473’s - and most of these credit card companies are already anti-gun, AND they’re already tracking your buying history and trends, so while your FFL is filing your 4473 for 3 years, a piece of paper in a box, your credit card company is actively analyzing your purchases, and isn’t so thrilled you’re buying guns at all…
 
all thats milled by the owner on an 80 is the fire control pocket. as long as you line up the trigger pin holes right and dont blow those out by wobbling the drill when youre cutting them... and manage to not cut your receiver down one side or the other with a hacksaw.... everything else there is basically cosmetic. you could do most of the work with a freaking drill press and some masking tape if you have more than 3 or 4 shiny brain cells to rub together.

the rest of the tolerance issues are those faced by the rest of the budget brand lowers out there, because the (metal) blanks are coming from the same forgings as almost every budget receiver on the market, and being milled to similar tolerance specs.


this is one of the very first receivers i ever milled and havent built out yet, just acquired as a 'do a fun build some day" lower, and this was before we got new tooling (some ham fisted fellow chipped a little corner off one of the mil flutes before i got to this)

so aside from the no anodizing, some mild tooling chatter and theres one little burr in the safety detent hole that i need to remove - i havent done *any* cleanup work on this one yet, this is raw, right out of the jig - this pocket is at least as acceptable as a poverty pony or other budget lower to house a FCG.

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@plant.one’s response here is exactly my point… Folks readily defend that it’s nearly impossible to mess up an 80% lower “if you have more than 3 or 4 shiny brain cells to rub together.” But then the same folks cast dispersions about lower cost finished lowers made on CNC equipment and cite these dimensional tolerance issues as the culprit… um… what? If we’re to believe it’s impossible to mess up, “even with a drill press,” then how do we believe it’s feasible CNC mills at professional manufacturing facilities still screw it up..?
 

thats the whole point - they do the precision needed stuff - and some do it well, others fail miserably - the stuff they leave for us poor pleebes to knock out on our 80% builds, is pretty big tolerance areas compared to what the CNC guys have to get right, and at much much much lower tolerance than anything the 80% crowd faces.



i dunno about people crying how a cheap stripped lower degrades performance. they're either gonna be in spec and work, or they're not gonna work at all because theyre too far out of spec.

accuracy - other than your choice of trigger group - doesnt come from the lower receiver group. 99% of the accuracy from an ar comes from

1) a good barrel
2) good barrel to upper receiver fit
3) a well mounted quality optic


so whatever performance gains you get comparing a $60 stripped lower vs a $200 stripped lower... i dunno where that comes from.


but hey... i clearly dont even know how to use a keyboard, no less use a trigger the right way, so i'll go back to polishing my 3 or 4 shiny brain cells i have left.
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Originally Posted By: Plant.One
thats the whole point - they do the precision needed stuff - and some do it well, others fail miserably - the stuff they leave for us poor pleebes to knock out on our 80% builds, is pretty big tolerance areas compared to what the CNC guys have to get right, and at much much much lower tolerance than anything the 80% crowd faces.



i dunno about people crying how a cheap stripped lower degrades performance. they're either gonna be in spec and work, or they're not gonna work at all because theyre too far out of spec.

accuracy - other than your choice of trigger group - doesnt come from the lower receiver group. 99% of the accuracy from an ar comes from

1) a good barrel
2) good barrel to upper receiver fit
3) a well mounted quality optic


so whatever performance gains you get comparing a $60 stripped lower vs a $200 stripped lower... i dunno where that comes from.


but hey... i clearly dont even know how to use a keyboard, no less use a trigger the right way, so i'll go back to polishing my 3 or 4 shiny brain cells i have left.
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i am in this camp.
 
Originally Posted By: Plant.OneOriginally Posted By: crapshootThe only plus is a non-traceable firearm.

with the way things are looking to be heading - or at least the way the anti-gun crowd would like them to go - thats a potential big value added feature for sure.

They've already been outlawed here locally in Clark County.
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Not illegal to own unfinished 80% lowers. Only illegal to have completed 80% lowers. Turn them in with no compensation or become a criminal.
 
Originally Posted By: crapshootNope

thats messed up. i'm pretty sure ven places like cali/wa state allowed them to be serialized and registered under their dumb laws.
 
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