LOWER RECEIVERS QUALITY

[Hulkstr8]

I personally have used Aero and Mega. I have also seen a bunch of other lower brands out and about.

Mega is hands down the best quality stripped lower I have ever seen. Also, awesome company. Jason Curns is a badass.

Aero -I'm personally torn. All three of my Aero lowers looks sweet with anodizing. However, when I had them cerakoted pitting, dents, dings, scratched, etc all showed up. My cerakote guy says it was in the metal. I don't trust him and he could have sprayed my parts wrong or ****ed them himself. However, I have no other experience with Aero.

I stick with forged because they're stronger than billet and I'm not chasing a trailer queen at this point in my life. College and no money lol.

[Artiz]

Hmmm, almost all of the original M16 were made from 6061.

6061 if more than adequate, strength-wise.

The originals were made of 6061 because the politicians who made all the production and fielding decisions were cheap shits who knew ****-all about guns and never listened to Stoner, Stoner told them to use 7075 T6 from the get go. When they realized the guns were literally disintegrating in the field, they switched to 7075.

Same thing for the lack of chrome in the chamber of the early guns, the use of the wrong kind of powder, those were political asinine decisions going against Stoner's recommendations.

[JC5188]

The originals were made of 6061 because the politicians who made all the production and fielding decisions were cheap shits who knew ****-all about guns and never listened to Stoner, Stoner told them to use 7075 T6 from the get go. When they realized the guns were literally disintegrating in the field, they switched to 7075.

Same thing for the lack of chrome in the chamber of the early guns, the use of the wrong kind of powder, those were political asinine decisions going against Stoner's recommendations.

Disintegrating in the field? What does that mean?

I make gates that weigh hundreds of lbs and are sometimes 40 ft long out of 6061...hooked up to operators and opened thousands of times over a lifetime. They don't just "disintegrate".

So, what are you referring to? Serious question, as I don't know everything.






"I've just got like, this 5.56 okay? And it's 55 grain ball. And everybody I've ever seen shot with it, it dicks them up."

---Clint Smith
Thunder Ranch

[Jellybean]

... For example, I read recently that Andersons are just as good as the others but are cheaper because Anderson doesn't advertise as much and therefore has to sell for less....

Not to dogpile on the Anderson 2-minute hate, but...
No, they're not as good as others.

A friend got one of there lowers just for the hell of it, to try to prove me wrong about the whole Price vs Quality thing. It was not impressive.
For one, the machining is "basic" for lack of a better word. Everything is very "square". I don't know how to explain it, but if you put it side by side with a better lower, it's very clear to see. Like they got 90% of the way through machining it and called it good enough and moved on to anodizing.
But that's forgivable.
What's not forgivable is then having to file away in various places to hand-fit your LKP once the assembly starts. Multiple areas where things were extremely tight, and the BHO could not be inserted at all into it's slot until filed.

Over the last 4 or five years I've built, or helped build about 6 Spikes lowers. They get a ton of hate here for some reason, and yet I have never seen issues like this with them. I'm not saying that to plug them (although I do consider them my go-to lower for budget builds), just to bridge into the second half of the story-

The builder I was helping also had 2 Spikes lowers, and 3 PSA LKP's to put in them all. I had a Spikes lower and a Sionics LPK (and was previously needled by the builder about "don't know why you had to pay $70 for that when the PSA kits are just as good...).
NONE of the PSA LKPs worked correctly- all had issues with poor parts machining and selection (springs to long, incorrect machining, metal hanging of parts where there shouldn't be metal hanging off, etc.). The owner then spent a couple weeks getting replacements from PSA because the first replacements had the same machining issues...
The issue with having to hand fit the parts in the Anderson? Tried the same parts in the Spikes lowers, and all fit fine.
The good news is after watching my lower go together with 0 issues, I think he finally saw the light...

I'm not saying you're *guaranteed* a failure if you buy cheap- if you want to take a chance, it's still a semi-free country and it's your money (use it when YOU need it... ), I just refuse to pay another cent for something that's not done right.

[AndyLate]

Disintegrating in the field? What does that mean?

In the book "The Gun", a Colt engineer who was sent to Vietnam to evaluate M-16 failures stated that the lower receivers were corroding so badly there were holes completely through the receiver walls.

Andy

[Artiz]

Disintegrating in the field? What does that mean?

I make gates that weigh hundreds of lbs and are sometimes 40 ft long out of 6061...hooked up to operators and opened thousands of times over a lifetime. They don't just "disintegrate".

So, what are you referring to? Serious question, as I don't know everything.






"I've just got like, this 5.56 okay? And it's 55 grain ball. And everybody I've ever seen shot with it, it dicks them up."

---Clint Smith
Thunder Ranch

They found out that in the hot and humid climate of Vietnam, the combination of sweat (and other fielded stuff they got on their hands) from the hands holding the receivers, over time caused the aluminium to undergo a chemical reaction called "Intergrandular Exfoliation", the receivers were basically corroding away and flaking off in layers.

[MistWolf]

In Vietnam, the original M16 used receivers made of 6061 aluminum, but later switched to 7075. The forging process makes 6061 alloy susceptible to intergranular exfoliation, especially in environments of high temperature and humidity. Exposure to human sweat only makes the problem worse. Upon a suggestion by Eugene Stoner, the receivers were changed to use 7075 aluminum. The 7075 alloy was designed to eliminate susceptibility to intergranular exfoliation in forgings.

[JC5188]

They found out that in the hot and humid climate of Vietnam, the combination of sweat (and other fielded stuff they got on their hands) from the hands holding the receivers, over time caused the aluminium to undergo a chemical reaction called "Intergrandular Exfoliation", the receivers were basically corroding away and flaking off in layers.

In Vietnam, the original M16 used receivers made of 6061 aluminum, but later switched to 7075. The forging process makes 6061 alloy susceptible to intergranular exfoliation, especially in environments of high temperature and humidity. Exposure to human sweat only makes the problem worse. Upon a suggestion by Eugene Stoner, the receivers were changed to use 7075 aluminum. The 7075 alloy was designed to eliminate susceptibility to intergranular exfoliation in forgings.

Would modern coatings not render that moot? As I mentioned, I sell (well, make...others sell) this material in MASSIVE qty to customers around the world. With no issue like y’all mention.

I’m not advocating 6061 receivers here, just that I have a lot of experience with this material. Primarily due to weldability.

Trying to learn.






"I've just got like, this 5.56 okay? And it's 55 grain ball. And everybody I've ever seen shot with it, it dicks them up."

---Clint Smith
Thunder Ranch

[pinzgauer]

Over the last 4 or five years I've built, or helped build about 6 Spikes lowers. They get a ton of hate here for some reason, and yet I have never seen issues like this with them. I'm not saying that to plug them (although I do consider them my go-to lower for budget builds),

Ummm, because they are more than double the cost of the Anderson's, and used to be 3-4x the cost?

It's not that I think Spikes currently is bad. It's just that for a long time you could do much better for less. Ex: you could buy a complete LMT lower half cheaper than you could buy parts from Spike to assemble one yourself.

They also publicly got caught stretching the term "mil-spec" to the limit on bolts and bcg's. Now are more in compliance, but did not handle it very well when it happened.

So you put known cheap lower receivers with known cheap lower parts kits and was surprised to find you had fit issues.

If you had tried known good lower parts kit and the Andersons and they didn't fit you probably have more of a case.

I'm not a fan of Anderson in general and specifically their lowers, though I bought one cuz it was just too cheap to turn down.

With Colt OEM and 69xx hovering in the $600-700 range, that sets a floor for me on building. And makes spikes a really bad deal.

I put the 6920 at $250 for complete lower, $100 for colt bcg, and $350 for the complete upper. With gold standard parts. Sometimes cheaper.

Spikes would charge you $430 for a complete lower. You'd be $300-350 to build one from parts.

Aero is my pick of late for cheap lowers, but only for oddball builds that don't start with a m4 type receiver extension.

[MistWolf]

Would modern coatings not render that moot?

No. The forging process does something to the granular structure of 6061 which starts the corrosion from the inside. The conditions in Vietnam didn't cause the corrosion in the receivers, they accelerated it.

As I mentioned, I sell (well, make...others sell) this material in MASSIVE qty to customers around the world. With no issue like y’all mention.

I’m not advocating 6061 receivers here, just that I have a lot of experience with this material. Primarily due to weldability.

Trying to learn.

6061 is a very popular choice for extrusions, bending and welding. I worked with a lot of sheet 6061t making instrument boxes for test aircraft. A tighter bend radius could be used compared to 2024T or 7075T and it can be welded for a seamless construction. 6061 simplifies forming parts because it can be bent up from sheetmetal that has already been heat treated without cracking. 6061 is more resistant to corrosion from the elements than 7075.

The downside to 6061 is it's not as tough as 2024 or 7075. 6061 is difficult to forge without incurring intergranular corrosion. 2024 and 7075 are better choices for making structural components. I cannot think of a single part of the primary or secondary structure of a Boeing 737 that is made from 6061.

7075 was developed for forgings. 7075 can be forged without causing granular damage. But, it's difficult to bend 7075 without cracking it. To bend up a part from 7075, O (annealed) material must be used and heat treated after forming. O material is difficult to work with because it's so soft, it easily wrinkles and ripples. It's harder to get clean flats and a smooth radius when bending than it is when using 6061T.

Each alloy of aluminum has it's job. 2024 is a good choice for forming the skins and structural sheetmetal parts for light aircraft. Simple parts can be formed from T material without cracking. 2024 is more economical than 7075.

7075 is more suitable for the primary structures of large and high performance. It's the alloy of choice to forge critical parts, such as the frames that hold the windscreens of jetliners in place, wing and engine mounts or where fuselage sections meet.

6061 is needed to form more complex parts quickly and economically that are not critical to flight safety. 6061 is an important alloy. It's just that, like 2024 and 7075, it works best used in the role it was developed to fill