AR 15 lower/upper questions

[DoubleJ]

I am cruising on Slickguns and I am seeing lots of complete lowers and uppers and it struck me, I don't know what I'm doing.  How do I know what I'm looking at and what lower goes with what upper?  Trying to put together an AR 15 as cheaply as possible.

Help me please.

[GregMcFadden]

Generally, assuming you are not looking to calibers of uppers that don't feed from "standard or standard outside shape" magazines any upper will work with any lower so long as both parts are in spec. 

Some of the pistol caliber uppers have specialized lowers and are by virtue of that, not usable with standard lowers.

[CastleRocker]

If you are looking to put one together from scratch, just stay with small pin Mil-Spec everything to start with and you will be fine.  (I bought a large pin upper one time by mistake just because it was "mil-spec"....wouldn't fit my lower). 

If you are looking for an inexpensive AR as your first one, look at the "bargin bin" at CMMG.  I've had two, and when I got them, they were less money than I could build one for, and most important, they were both good rifles.

Just be aware, AR's are like Lego's were when you were a kid, and one set won't be enough!  Pretty soon you will have all kinds of Picatinny rails and stuff to attach to it, extra stocks, forends, barrels, and you will have always have either more uppers than lowers or the other way around.  I tell my wife that I have no control over it....this stuff keeps reproducing in the safe!  It's all good now though, as she wants another one herself.

[Todd_ID]

I started at square one not too long ago, also.  Basically any lower will work with any upper as long as you don't get an odd caliber.  AR-15 and AR-10 parts are not interchangeable.  Cheapest lower I know of is PCF (Plum Crazy Firearms).  It's all carbon fiber and is $120; probably won't find a cheaper one anywhere.  I read an article about them, and the writer really liked it, but that's all I know about them. 

One thing to keep in mind is that buffer tubes and stocks come in two sizes: mil-spec and commercial.  Either is fine, just know which you're getting if you buy a stock, buffer spring, buffer tube, or buffer separate.  Your cheapest bet is to put the parts together yourself for the most part unless you find a steal on a complete upper or lower, and it's not hard or complicated with plenty of instructions online.  You'll generally save maybe $50 by putting it together yourself; plus you get to learn all about every part of your rifle.

Bravo Company USA is a great go-to place for low price and high quality.  They get very high quality marks in all the reviews I've seen.

Gas tubes come in different lengths based on where the rifle pulls the gas out of the barrel.  There's literally a hole drilled into the barrel where the gas exits, hits the gas block, goes down the gas tube and hits the gas key to cycle the action.  Carbine length is closest to the action, mid-length is a bit further out, and rifle length is the farthest down the barrel.  As general rules of thumb: carbine operates the bolt the hardest and fastest (less likely to jam, but parts wear quicker); rifle length slows the bolt down better because of lower gas pressure so feed problems are less likely in full auto; mid-length was developed as the best of both worlds.

Feed ramps are either M4 or standard.  M4 was developed to reduce feed jams in .223 at high fire rates.  Hard to find standard ones now though since M4 works well.  The feed ramp is only important when choosing a barrel and upper receiver separately; if you get a complete upper assembly, then they'll have the right ones there already.

[DoubleJ]

So, if I get this:

http://www.colemantyler.com/proddetail.php?prod=PCLRC6

And this:

http://www.elitetacticalcomponents.com/ar-15-complete-uppers/dti-ar-15-16-complete-upper-1-9-twist-chrome-moly-dt1009-s.html

I'll be good to go?

[Jamieb]

With those two, is that a coplete, ready to fire ar-15 for under $500?

[Todd_ID]

I'd say yes, that'll work.  $499 is about the same as a Del-Ton setup if you can find a cheap stripped lower.  With the ones you've found you won't have to put it together.  I say go for it for a super cheap entry price.  Don't forget a rear sight is $100 for a decent one.  No such thing as a cheap AR, though.  I'm $2000 into all my stuff with the .50 Beowulf upper plus 1750 rounds of .223 ammo, Beowulf brass and bullets, scopes, reloading supplies, etc., and I bought a cheap rifle to start.

[DoubleJ]

When ordering it as an upper and a lower, is an FFL still needed?

[huntandjeep]

yes for the lower.

[micdude]

Buy the upper complet and put the lower together yourself there is a ton of stuff on youtube showing how to put a lower together, leave the the uppers alone till you gain some knowledge.

Best deal on an upper is a spikes for 499.00 w/BCG
Lower go Areo Pacific and get it from Ammo surplus 74.99
 From PSA MOE lower build kit 139.99 or classic for 99.99

For about 720.00 you can have a really good rifle.

Parts:

http://palmettostatearmory.com/598.php
http://www.surplusammo.com/products/%2ASurplus-Ammo-%26-Arms-AR15-Stripped-Lower-Receiver.html
http://www.primaryarms.com/product.sc?productId=575&categoryId=94

[dannysdaddy]

when you say as cheap as possible, how much are you looking to spend max and what are you willing to sacrifice in quality to get that price? 

[DoubleJ]

I've actually decided to go with an AK 74.  Cheaper gun, cheaper ammo, lower recoil, same, if not better ballistics.  An AR is still on the radar for me, I'm just going to have to put it off for awhile.  I only had $450ish to spend.

[383man]

I've actually decided to go with an AK 74.  Cheaper gun, cheaper ammo, lower recoil, same, if not better ballistics.  An AR is still on the radar for me, I'm just going to have to put it off for awhile.  I only had $450ish to spend.

AK 47?

[Dirty Mike]

ak74 shoots223

[chrisb]

ak74 shoots223

The AK 74 shoots the 5.45 x 39 where the "general" metric conversion for 223 is 5.56 x 45.

There may be some out there chambered in 5.56 but in general they are 5.45 rifles IIRC