Uppers and Lowers

[Grittydog]

Can yall list a few of the best lowers and uppers that are on the market. I wanted to buy a complete Ar until I found this site. Now I am going to build my own, actually 2 my hunting partner wants one also. I was looking at the Mega Arms uppers and lower, but what are some of the better ones out there? I want to build it right the first time. Thanks, James

[Bob Reed]

COLT is the highest quality available and the only thing that tops a COLT, is a Special Production COLT from Specialized Armament.

You can get everything you need from Specialized Armament, and you can buy from them with confidence! http://www.specializedarmament.com/

And regardless of what you may read - all the "off-brands" fall short one way or another when compared to COLT.

[TangoSauce]

Can yall list a few of the best lowers and uppers that are on the market. I wanted to buy a complete Ar until I found this site. Now I am going to build my own, actually 2 my hunting partner wants one also. I was looking at the Mega Arms uppers and lower, but what are some of the better ones out there? I want to build it right the first time. Thanks, James

Noveske Gen2 lower/Vltor MUR upper (or hand-matched N4 set on a budget)

LaRue Billet lower/upper (M4 ramps available on skdtac)

Rainier would be high on my list too.

[chazthebiker]

I have two Mega Machine Billet based rifles, one is the monolithic upper and the other has a DD Lite Rail. I also have a Noveske upper / lower matched set with a Larue rail. All are very nice, but I cannot say how they fall short. I can only speak to what I own. Mine have not failed me. I am unaware of any studies or statistics that show how or why one brand is better than another. There are anecdotal reports of failures for most any brand. There is "The Chart" to consider, and I believe it to be an excellent guide to steer one towards quality parts. The man who put "The Chart" together did everyone a great service. The chart pertains to internal parts, I think (have not looked in a while. Some swear by Colt, some by Noveske, some by LMT. My opinion is this; Buy quality internal parts and you should be fine in any senario or class. Buy cheap or bargain basement and you may or may not have problems. The biggest thing to remember is this; get what YOU like after you have done your own research and combed through the opinions of others who have owned various brands and configurations. Watch out for fan boys. In my opinion, the internal parts will impact reliabilty more than the brand name roll mark on the lower.

Would I buy Colt, LMT, or Noveske? In a minute... any of them. Would I buy Mega again if I could? Dang right I would.... in a minute! Would I buy Stag, Bushmaster, S&W? Probably not... but not because there might be anything wrong with them. I like to assemble my own. If I am doing that, then I will buy the roll mark that pleases me most. What would I buy if buying a complete rifle? Noveske, hands down, just because that is what I like and I don't have to look at that funny grenade launcher notch on the barrel.

Just have fun! Buy quality internals and for the upper / lower: just get the brand name roll mark you prefer. BTW, I have seen the Rainier uppers and lowers. They are very nice too. If you are going to buy and assemble yourself, I cannot give a higher recommendation than folks at Rainier Arms as a parts source. I do, however, recommend the Spike's Tactical lower parts kit.

Have fun!

[AR-10]

Here's why Colt is the best:

0.170" fire control pins
Two-piece pivot pin that is larger than it should be
Lower receiver that isn't even drilled for a pivot pin detent
Lower receiver finish that appears as if someone pressed it against a belt sander before hard anodize
Sear block in lower receiver that forces you to run special bolt carrier with a totally open bottom

I've done the Colt thing, now I put together my own - and I happen to use forged Mega receivers.

Bravo Company and Daniel Defense both offer hammer forged barrels that are every bit as good as a Colt.

[Grittydog]

Thanks for the replies so far, How much difference is there between a Billet and a Forged? Can 1 rifle shoot 2 different calibers(5.56 & 6.8SPC) if you have 2 complete uppers? Thanks, James.

[Creeky73]

I wouldn't get all caught up in the billet stuff. If you can catch something on sale and get it close to the same price as a good forged, that is one thing. Otherwise, billet is pretty much to make people ooh and aah at the range. The only thing I got from my billet lower that I give a hoot about is the machined trigger guard, which isn't that big of a deal.

I would suggest buying a matched set on the stripped upper and lower if you are going to build. I found out the hard way that some parts match up better than others, and I had some pretty huge gaps between the halves. Pretty hard to feel good about a $1500 build when you could read a newspaper through the middle of your weapon.

[AR-10]

Stick with forged receivers unless you have an unlimited budget or you want a rifle that really stands out from other AR's.

Using the same lower for 5.56 and 6.8 is no problem at all, swap uppers and magazines and you're done.

[Bob Reed]

Hello AR-10,

COLT went back to the standard FCG Pins and Pivot Pin a long time ago. They also dropped the hardened sear-block and went back to shipping the guns with M16 Carriers, but they still folded when it came to giving us a regular receiver. Now they have a sear-blocking-cross-web in the lower in order to keep the "bed-wetters" from having complete nervous break downs!

Despite that, COLT does have the highest-quality parts - and that's what matters the most.

Take a couple of complete sets of COLT Parts and a couple of complete sets of the other makers parts into an inspection room that's equipped with high quality micrometers, calipers, pin gages, height gages, radius gages, hardness testers, surface gages and comparator machines and see what you have with these off-brands when comparing them to COLT.

COLT'S Hammer Forged 7075-T6 Receiver Extensions have bore's that are machined mirror-smooth which creates a smoother-cycling weapon and the threads on the RE are full-cut and give proper (full) thread engagement with the threads in the lower which in turn creates a stronger union.

COLT Pistol Grips, Military-Grade Stocks & Handguards are also made from higher quality, better materials.

COLT Factory Supplied (OKay Industries) Magazines are made to higher standards and have better springs than the flimsy off-brand magazines and the dull-mint colored followers in the 30-Rd. COLT Mags are molded better and have less molding-flash than the (cheap) aftermarket bright-green followers.

I actually happen to be a machinist and know first hand what's involved in producing high-quality, close tolerance parts and these so-called "just as good as" guys aren't doing it.

[Grittydog]

When I am finished with my build I want it to look simular to this one, or like the ones Stickman takes pictures of. I found this site through a picture Stickman had posted. It will probably take me 6 months to get all the parts. I appreciate the information that has been given and I will use the venders that have been recomended on this site.
http://i303.photobucket.com/albums/nn137/grittydog/DD_Spikes_AR15.jpg

[Stickman]

I actually happen to be a machinist and know first hand what's involved in producing high-quality, close tolerance parts and these so-called "just as good as" guys aren't doing it.



The problem isn't that you are a machinist, it is that you don't know the weapon industry. If you were dialed in with Colt, you would have information on who they subcontract with, and you would understand who else uses those same companies and the same standards.

Colt makes a great product, and I certainly agree they make a good product, but so do others.

[lamarbrog]

Wow. I happen to be a pretty good fan of Colt rifles and parts, too, but that's a level of Pony Lovin' I had not witnessed until now...

When it comes to stripped upper and lower receivers, most companies are putting out a quality product. (It's apparently difficult to screw up taking a piece of aluminum, drilling some holes in it, and anodizing it.) The proper forged 7075-T6 aluminum alloy is pretty much standard across the industry. The days of cast lowers seem to be behind us, as they have been for some time. As long as you manage to avoid plastic lowers, you shouldn't have any major issues from any of the reputable companies.

One thing I would mention is that some companies only anodize, while others anodize and then apply a Teflon finish. My preference is for an absence of Teflon since it is lower gloss and is generally just more subdued. Whatever lower you get, I would make sure the upper has the same finish, otherwise it looks really funky. It's not a functional issue, but why make a rifle look like a hack job when it doesn't have to?

So, pick what kind of finish you prefer. Then, see which reputable companies sell uppers and lowers with that type of finish. Beyond that, pick based on either price, or which roll mark you want stamped on the side.

I don't like flashy stuff, so I picked Interarms. They don't Teflon, and their roll mark doesn't have anything other than the word "Interarms". I've also had good luck with CMMG, and Double Star.


If you're going to get picky and meticulous (as you should) focus on your barrel, and bolt carrier group. Beyond that, focus on the lower parts kit. Different manufacturers on those parts genuinely do make a big difference. The receivers themselves are all about the same. If the parts fit in the holes and move as they are supposed to, and it's 7075-T6 that's at least anodized... it's cosmetics beyond that.

[AR-10]

Bob, I am aware that Colts do not ship with those oddball features anymore which is great since they drove away potential buyers.

Point is, there are thousands of Colts out there to do have these weird features and I've owned a few.

That being said, I use Colt lower parts exclusively in my lower receivers and if Colt actually made a 6-position receiver extension I would probably buy them because I believe they make one of the strongest. I can't live with 4 positions on my carbine stocks, so I buy my tubes from somewhere else. I should add that Colt isn't the only company that actually hones the i.d. of their receiver extensions to feel like glass.

Just take a look at these two forged lowers, Mega on top with a Colt below it:

http://i41.tinypic.com/nwlrbl.jpg

Both are cut from 7075-T6 forgings and all dimensions are correct.

Both are hard anodized so one is not more durable than the other.

Now if you want to start nitpicking, look at the bevel on the magazine well and take a look at the forging flash that Colt leaves inside the trigger guard.

Do I care about the cosmetics? Not really, but I don't agree with calling something "the best" when there are clearly options that are just as good if not better.

[chazthebiker]

I would like to see some kind of study documentation comparing the measurements of parts and hardness of various parts as compared to "mil spec". While we are at it, I would appreciate knowing where I can find the mil spec for these weapons. I have searched and searched. For instance: Is the Colt 6920 made to mil spec? It isn't made for the military. So what is the standard. The fire control group can't be milspec because it does not allow automatic fire. What is the hardness of various parts supposed to be? There may be manufacturers out there who far exceed the "mil spec" standard.

I used to work in the printed circuit board industry. When we got a military order for a board "mil spec" generally only meant "this is what they want and what they want it to do and the MINIMUM PERFORMANCE SPECIFICATIONS".

In other words "mil spec" simply means "customer specifications" (when the customer is military). It doesn't mean the best, the greatest, or anything other than what a particular customer wants. Cisco specs what they want this way, Motorolla that way, the Air Force another way, etc.

So I would imagine that if Colt is the main supplier of rifles to the military, that they meet at least the minimum "mil spec". I would also imagine that if other manufacturers are trying to take a piece of that DOD pie, that they may be working real hard to out do whomever the top supplier is. This may mean beating the quality with better or more refined parts.

I know nobody has even mentioned "Mil Spec" in this thresd, but isn't that really the implication? "Mil Spec" is not the goal, I hope. Certainly COMPETITION between the various serious players in the industry is pushing the platform far beyond that. Frankly, I don't put much stock in "mil spec" because nobody has shown it to me, and I would wager most folks that throw around the term have never seen it. "So and so's widget is "mil spec". Why? because they say so? Because the guy who is singing the praises of that particular widget wants it to be "mil spec?"

Bob, do you have any comparison data you have gathered you could share with us? I am guessing that since you mentioned the tools of your trade in conjunction with Colt and this thread subject matter that you have done some comparison studies and documented them? How would one know that the hardness of a Colt hammer is correct vs. brand X? How does the "Mil Spec" for rifles Colt supplies to the military compare to what the "Colt Spec" is for law enforcement or civilians?

I am not picking on you Bob. I really want to know. How do we KNOW?

Thanks.

[Casull]

Although they are not the only ones, Daniel Defense makes great stuff, and their lowers feature the slightly flared magwell just like the Mega. To me that expresses attention to detail in their products that goes further than some of the best. Like Colt!

Frankly, however, you can get any reputable maker's upper and lower and have peace of mind. Just be sure that when you get you upper that has the correct feed ramps for your barrel. Most are M4 style these days. This is considering you are buying your own barrel separate and not attached at the factory.