556 80% AR Lower receiver build

[lazarus]

thanks i will take a look. i seen alot of places sold out of the 80% it may just be what i can find for now will have to work and ill have to get a better if i don't like it when they are in stock.

I understand some of the reasons of wanting an 80%, but any particular reason not to look at a finished lower? Probably one of the IPs on here or a shop around you either has one for a pretty reasonable price or could get one. JLowes is quite a drive from you, but I picked up a pair of Anderson lowers for $100 not too long ago from them.

I'd like to build an 80% at some point, but really just because I enjoy building things.

 

[matt-maniac]

i have access to a CNC so it will not be hard to build one and it will be a good learning experience. im not in any rush i just wanted somthing to build and work on in my spare time. i still have to get a HBAR barrel and some other things to build

 

[Ranchero50]

Yeah, I just downloaded an .IGS file for a GI lower and finally got OneCNC installed on the new shop puter so this might get interesting. I've been too lazy / poor to buy a kit to QA a 0% or 80% lower build. Now I'm running out of excuses...

 

[Viper21773]

80percentarms.com, 80-lower.com and daytonatactical.com seem to have stock.

 

[GTOGUNNER]

Sports N Hobbies in Frederick carries 80% lowers. They're by SUB.MOA (Cerro "keyhole" marked).

Any idea what they are charging?

 

[lazarus]

i have access to a CNC so it will not be hard to build one and it will be a good learning experience. im not in any rush i just wanted somthing to build and work on in my spare time. i still have to get a HBAR barrel and some other things to build

Seems like a pretty good reason :-)

Heck, I built my first AR-15 because I wanted to learn how.

That said...I probably caught a fever or something there. Don't know if I'll ever buy a pre-made AR-15. Building them is just so much fun.

 

[2nd=Good+Substantial]

Any idea what they are charging?

$90 - bead blasted forged
$95 - bead blasted billet
$100 - black anodized (forged or billet)
$130 - FDE cerokoted billet.

 

[CSHS]

I've been happy with Tactical Machining 80 lowers.

 

[fabsroman]

The 29'' thingy is for SBRs in Md. nothing else. Only length requirement for your friend's gun is that it has a barrel measuring at least 16'' from closed bolt face to end of muzzle if it will have a stock on it.

The 29" thingy isn't only for SBR's in Maryland, it applies to all semi-automatic centerfire rifles. Take a Ruger Mini 30 and make it shorter than 29", and you are in trouble. I believe there are some 16" barreled bullpups out there that do not meet the 29" requirement and are therefore banned as a "copycat".

Now, the likelihood of an AR-15 with a 16" barrel not making the 29" requirements is pretty slim. The stock would have to be short as can be.

 

[Doitsouthstyle]

The 29" thingy isn't only for SBR's in Maryland, it applies to all semi-automatic centerfire rifles. Take a Ruger Mini 30 and make it shorter than 29", and you are in trouble. I believe there are some 16" barreled bullpups out there that do not meet the 29" requirement and are therefore banned as a "copycat".

Now, the likelihood of an AR-15 with a 16" barrel not making the 29" requirements is pretty slim. The stock would have to be short as can be.

Tavor SAR and X95 for explain in there original form.

 

[outrider58]

The 29" thingy isn't only for SBR's in Maryland, it applies to all semi-automatic centerfire rifles. Take a Ruger Mini 30 and make it shorter than 29", and you are in trouble. I believe there are some 16" barreled bullpups out there that do not meet the 29" requirement and are therefore banned as a "copycat".

Now, the likelihood of an AR-15 with a 16" barrel not making the 29" requirements is pretty slim. The stock would have to be short as can be.

You are correct. I was being too vague. I edited my post.

 

[Jkratz]

something that has probably been asked before..but i have never seen it discussed...if u throw a HBAR marked barrel on a post 2013 lower and even have proof (an add/receipt) and it turns out someone used a HBAR stamp to swindle people..would the owner have legal troubles?...i say this as the only non pre 2013 lowers are NFA items and the only 556 version is still in jail....it just seems like everyone only cares about that mark which in theory could be easy to reproduce-

 

[eruby]

Since it is marked HBAR and was advertised as such, you should be okay.

But to quote Dragline from Cool Hand Luke, "when it comes to the law, nothing is understood."

 

[fabsroman]

something that has probably been asked before..but i have never seen it discussed...if u throw a HBAR marked barrel on a post 2013 lower and even have proof (an add/receipt) and it turns out someone used a HBAR stamp to swindle people..would the owner have legal troubles?...i say this as the only non pre 2013 lowers are NFA items and the only 556 version is still in jail....it just seems like everyone only cares about that mark which in theory could be easy to reproduce-

I would be very cautious of using any barrel that does not measure at least .750" throughout or that has a M203 cutout on it, even if it is marked HBAR.

This entire HBAR thing has been a back and forth with MSP with no real definition of HBAR. I would prefer that MSP provide us with a nominal dimension for HBAR and call it a day.

 

[lazarus]

I would be very cautious of using any barrel that does not measure at least .750" throughout or that has a M203 cutout on it, even if it is marked HBAR.

This entire HBAR thing has been a back and forth with MSP with no real definition of HBAR. I would prefer that MSP provide us with a nominal dimension for HBAR and call it a day.

That would be nice. Everything I have read is their opinion is if it marked HBAR or advertised as HBAR it is ok. Either or. Does. It have to be both.

Just giving us fixed dimensions would be nicer. But as mentioned, it is nominally no less than .750" in diameter the entire length of the barrel until the threading.

There are a couple of rifles sold as heavy barreled or HBAR that are less. Frankly I don't want to chance it.