PDA

View Full Version : Honest truth about billet uppers



5pins
02-08-11, 21:00
The “honest truth about SS barrels” thread started me thinking about the claim that billet uppers improve accuracy.

I have not seen any evidence to support the claim and was wondering if anyone has any info that it’s true.

I guess I’m asking if there is any reason to get a billet upper over a standard forged upper.

ucrt
02-08-11, 21:24
.

This is what I understand:

The aluminum used in a billet is not as strong as the aluminum in a forging.

To compensate for this weakness, a billet is beefed up in key areas which make them stiffer and stronger than a forging. This stiffness contributes to the billets accuracy. A beefed up billet is also it heavier than the forging.

Because a billet is beefed up, it does not have the same external "profile" as a forged part. Not having the same "profile" may prevent some attachments, aftermarket items, etc. from working; such as: BAD Levers, ambidextrous devices, etc.

So...the billet does have a good reputation at being more accurate at the expense of being heavier and not having mil-spec external dimensions.

This is all info you probably knew, if so...sorry.

.

Fried Chicken Blowout
02-08-11, 21:35
.
Because a billet is beefed up, it does not have the same external "profile" as a forged part. Not having the same "profile" may prevent some attachments, aftermarket items, etc. from working; such as: BAD Levers, ambidextrous devices, etc.
.

Funny you should mention this. I just happened to be looking at a set of billet upper/lower today and noticed that I didn't think my Wilson Combat extended bolt release would fit due to a change in external profile. I guess I could live with that, but if I lost my ambi mag release, that would be a deal killer as a left handed shooter.

ALCOAR
02-08-11, 21:36
Ive yet to hear any honest truths in regards to a billet being more accurate than a forged one. Lets just assume the billet one is more accurate....how much more accurate exactly would a naked billet upper receiver be as a single component on a particular build over the forged upper receiver given it's machined to proper tight specs? My guess is not much if any at all, but then again I really don't have a dog in this fight since I only use mrp tops.

Militant83
02-08-11, 21:37
I was going through this very same debate while choosing parts for my new build. I dont see a billet being that much more accurate than a forged if it is at all. I ended up going with a forged. I couldnt get myself to pay in most cases 3 times more for a billet receiver.

bp7178
02-08-11, 21:50
+1

I went with a matched forged set for this very reason. I want to use a BAD lever. The reason I didn't buy a Larue upper/lower was, in part, related to the ability to mount such parts.

Fried Chicken Blowout
02-08-11, 22:09
how much more accurate exactly would a naked billet upper receiver be as a single component on a particular build over the forged upper receiver given it's machined to proper tight specs?

I don't think there would be any single shot improved accuracy. But in theory a stiffer platform would result in tighter multi-shot groups due to less deflection from zero. This would be my unproven theory...

ALCOAR
02-08-11, 22:38
I certainly agree that the stiffness or as I call it rigidity in a platform is paramount to it's accuracy/precision..again, it's why I'm a mrp guy.

That said, so many more important factors will influence a precision build ahead of this particular naked upper receiver be it forged or billet like the barrel, the ammo, the shooter/trigger, etc. In less the billet upper receiver incorporates a totally different barrel hookup with more barrel extension captured... than it really cannot stiffen the platform that much more, if any at all imo.

eta...obviously if it incorporated a new barrel hookup that captured more barrel extension...it would need special barrels:)

5pins
02-09-11, 09:42
Pretty much what I thought. No conclusive evidence that billet uppers enhance accuracy in a meaningful or measurable way.

So why so popular. They are bigger, heaver and cost more, yet they seem to be a big deal right now. So do they bring any benefit over forged uppers?

Militant83
02-09-11, 10:05
Pretty much what I thought. No conclusive evidence that billet uppers enhance accuracy in a meaningful or measurable way.

So why so popular. They are bigger, heaver and cost more, yet they seem to be a big deal right now. So do they bring any benefit over forged uppers?

A lot of people like the looks of them. Billet is milled and they can mill different designs can easily be milled into them. But again all of that is also what makes them more expensive.

Johnny Thujone
02-09-11, 12:03
Not to put words in anyone's mouth, but i remember Wes Grant talking over at TOS about how milled uppers were "straighter" more consistently than their forged brethren. He used it just like that, putting straighter in quotations and not really delving further into exactly what it meant, but i'd take it milled uppers have more consistent tolerances upper to upper (At least, LaRue and VLTOR uppers do, which are the two he uses.).

I figure, if someone knows something about accurate ARs, it's him.

Skyyr
02-09-11, 13:29
Not to put words in anyone's mouth, but i remember Wes Grant talking over at TOS about how milled uppers were "straighter" more consistently than their forged brethren. He used it just like that, putting straighter in quotations and not really delving further into exactly what it meant, but i'd take it milled uppers have more consistent tolerances upper to upper (At least, LaRue and VLTOR uppers do, which are the two he uses.).

I figure, if someone knows something about accurate ARs, it's him.

Uppers, yes. Lowers, no. There's nothing about the lower that contributes to the inherent accuracy of the upper.

Hmac
02-09-11, 14:01
As I understand it, the stress relief involved in the forging process makes for a stronger upper given the same amount of aluminum. I guess I'd always think that a billet upper or lower was a cosmetic choice, not a functional one.

If I thought rigidity were something important that my skills could take advantage of, I'd get a VLTOR MUR with or without a VLTOR VIS long before I'd go with a billet upper.


/

ALCOAR
02-09-11, 14:54
A lot of people like the looks of them. Billet is milled and they can mill different designs can easily be milled into them. But again all of that is also what makes them more expensive.

DING...I put my money on this almost exclusively being the deciding factor for why somebody buys a billet.

I want a dimpled barreled billet upper receiver:D:D

mstennes
02-09-11, 15:33
Not to put words in anyone's mouth, but i remember Wes Grant talking over at TOS about how milled uppers were "straighter" more consistently than their forged brethren. He used it just like that, putting straighter in quotations and not really delving further into exactly what it meant, but i'd take it milled uppers have more consistent tolerances upper to upper (At least, LaRue and VLTOR uppers do, which are the two he uses.).

I figure, if someone knows something about accurate ARs, it's him.

The problem I have with that, is even raw forgings, have to be milled to their finish specs, if the CNC program is correct, and the equipment doing it is in good order, how could a billet be straighter than a forged unit?

BaileyMoto
02-09-11, 16:31
Plenty of 'run of the mill" and "off the shelf" upper receivers are built and shot to .5 MOA (and better). I'd LOVE to see a measurable difference by someone who claims a billet upper receiver is producing better accuracy. I'm staying away from this kool-aid for now. :)

Johnny Thujone
02-09-11, 18:25
The problem I have with that, is even raw forgings, have to be milled to their finish specs, if the CNC program is correct, and the equipment doing it is in good order, how could a billet be straighter than a forged unit?

VLTOR are forged (Per their site.), so i was wrong in my statement.

Looking for the exact quotes, but i suspect that it's dependent on the manufacturer holding unit to unit tolerances and VLTOR and LT happen to do it much better than most, even though VLTOR is forged and LT is billet.

Militant83
02-09-11, 19:21
DING...I put my money on this almost exclusively being the deciding factor for why somebody buys a billet.

I want a dimpled barreled billet upper receiver:D:D

Its crazy what people will do for looks.. And I cant say it hasnt crossed my mind before. But my thought is save some money and get a forged and take the money you saved and put it into a better optic or other quality parts.

mstennes
02-10-11, 00:08
VLTOR are forged (Per their site.), so i was wrong in my statement.

Looking for the exact quotes, but i suspect that it's dependent on the manufacturer holding unit to unit tolerances and VLTOR and LT happen to do it much better than most, even though VLTOR is forged and LT is billet.

True, but if its milspec than it HAS to be to the specs, so any top tier manufacturer would be good to go, now bets are off once you drop down to second or third tier, thus the reason they are there in the first place.

ETA, like said in the SS barrel thread, you pay for quality.

Sry0fcr
02-10-11, 08:21
I think the honest truth is that the advantages are probably more theoretical than practical. There's probably no real "need" for them, but so long as they don't negatively affect function I don't have any beef with people using them.

500grains
02-10-11, 08:53
The “honest truth about SS barrels” thread started me thinking about the claim that billet uppers improve accuracy.


Stiffness improves accuracy.

Example: VLTOR VIS

K.L. Davis
02-10-11, 09:13
Billet (https://www.m4carbine.net/showthread.php?t=611&highlight=billet)

czydj
02-10-11, 09:29
Billet (https://www.m4carbine.net/showthread.php?t=611&highlight=billet)

For the WIN!

/thread closed

mstennes
02-10-11, 11:41
Billet (https://www.m4carbine.net/showthread.php?t=611&highlight=billet)


For the WIN!

/thread closed

How do you figure? Why would a VIS be any stiffer? The barrel still mounts at the front of the reciever via a nut on a threaded extension billet, cast or forged.

Fighting Tenth
02-11-11, 21:42
The upper and lower receivers are cases. They neither detract nor add to the accuracy of an AR.

mstennes
02-12-11, 11:09
The upper and lower receivers are cases. They neither detract nor add to the accuracy of an AR.

The upper does, but is billet stronger or better? IMO no, actually if done to exact deminsions its weaker, thus billet is always bigger, therefore its not to milspec. Which also brings another question, are "matched" upper and lowers better? Again IMO no.

Hmac
02-12-11, 11:31
Which also brings another question, are "matched" upper and lowers better? Again IMO no.

From a functional standpoint, I agree, but for example, a matched Noveske upper/lower is $275. A Noveske upper by itself is $135, a Noveske lower is $185.

I bought my last Noveske matched upper/lower for $250 (waiting on USPS to deliver another one to my FFL that I just bought for $275). They fit perfectly. I know, I know..."a little bit of play between upper and lower is no big deal and only a noob, tactical wannabe would complain about it". I completely agree that the wobble makes no difference in function, but generally, we all consider a lack of rattling in our consumer products to be a sign of quality. In the process of saving $45, I also can get the satisfaction of a nice precision fit.

mstennes
02-12-11, 11:54
From a functional standpoint, I agree, but for example, a matched Noveske upper/lower is $275. A Noveske upper by itself is $135, a Noveske lower is $185.

I bought my last Noveske matched upper/lower for $250 (waiting on USPS to deliver another one to my FFL that I just bought for $275). They fit perfectly. I know, I know..."a little bit of play between upper and lower is no big deal and only a noob, tactical wannabe would complain about it". I completely agree that the wobble makes no difference in function, but generally, we all consider a lack of rattling in our consumer products to be a sign of quality. In the process of saving $45, I also can get the satisfaction of a nice precision fit.

Agreed! If you shop around or know what your doing, you can save, problem is, most people have no clue, and resalers know it, so they will actually raise the cost. I have noticed, if you stay with tier one manufacturers, who actually follow milspec, there is so little movement between uppers and lowers anyway. Jeese a friend of mine just got a new LMT and there is no rattle or wiggle, it almost feels like it has a wedge in it.

Fighting Tenth
02-12-11, 18:52
The upper does...

Does what? Affect accuracy?
In all my shooting, testing and reading I have yet to see this in function. Near as I can tell it is barrel and bolt.
Where and how has it been shown that an upper receiver will affect the accuracy of the system of components?

mstennes
02-13-11, 12:44
Does what? Affect accuracy?
In all my shooting, testing and reading I have yet to see this in function. Near as I can tell it is barrel and bolt.
Where and how has it been shown that an upper receiver will affect the accuracy of the system of components?

What does the barrel attach to? The upper, if the upper is out of whack, that will effect accuracy. What happens if the upper is flexing? What it its not on but off a little?

Fighting Tenth
02-13-11, 13:37
What does the barrel attach to? The upper, if the upper is out of whack, that will effect accuracy. What happens if the upper is flexing?

Yeah, I suppose theoretically this could happen - I just haven't seen it in practice.
Does anyone (like perhaps the USAMU) have any hard evidence to support this happens?

mstennes
02-13-11, 16:05
Yeah, I suppose theoretically this could happen - I just haven't seen it in practice.
Does anyone (like perhaps the USAMU) have any hard evidence to support this happens?

I do sorta, I guy here brought in his Model 1 parts kit to be built. After I had it up and going it never would group worth a shit, and made a funny noise. I took it all back apart and couldnt see a thing wrong, so I swapped in a barrel I knew that was good, same problem, so I kept looking and never could see anything, untill I started measuring, and low and behold it was off, and I also noticed under a magnifing glass it little stress fissures in it by the barrel area where it was flexing under load.

MistWolf
02-13-11, 18:39
As the optics and/or rear sight is normally mounted to the upper receiver, if the receiver does not consistently hold the barrel assembly there will be a shift in the point of impact. The upper receiver could possibly affect barrel harmonics also causing inconsistencies in the POI

Cesiumsponge
02-19-11, 11:47
Let me chime in from a manufacturing standpoint.

Forging creates a denser metal grain structure when the metal flows under forging pressure and orients surface grain flow to follow the curvature of the features forged into the blank. It increases strength. The same strength gains can be seen in other manufacturing techniques that plastically deforms the material being processed, such as hole mandrelizing, button rifling, thread rolling, cold-form tapping, etc. It's all run-of-the-mill processes used in commercial and aerospace manufacturing. None of it is unique to the firearms industry. You'll find a lot of folks in the automotive hobby tend to have a lot of wild ideas about billet parts too. While not a direct comparison, spun cast aluminum alloy wheels and forged aluminum alloy wheels have a huge weight disparity (and pricing too) because forgings can "do more with less".

Machining from a blank is nice because the shape is up to what the engineer and programmer wishes to do on the machining center. You can do smaller runs while keeping reasonable costs-per-unit because you're just investing in additional programming time and not new tooling if you change the design. Forging is a pretty expensive process to set up. Making any changes requires the manufacturing of a new set of forging dies.

The accuracy is up to the engineers. Mil-spec receivers are stuck to a specific shape and set of tolerances and cannot add anything extra without falling outside the print dimensions. Billets can be stronger than forgings simply because they can leave more material, can reinforce areas that are prone to deformation, and aren't limited to the blueprint shape of the receivers so it's not really an apples-apples comparison. If you have a forging of identical mass and shape to a billet, it'll be stronger than the billet. Forgings receive further machine work to clean up dimensions, true up holes, and whatnot so any meaningful tolerances in regards to flatness, parallelism, etc, is determined by the print specs and how tight the machinist wants to hold those specs. A tolerance might be -/+ 0.010" so a part held at +.0095" is just as good as a part that measures -0.0003" because it's within print specs. If it takes additional time and effort (which translates to money) to hold smaller tolerances than the print allocation, it makes no financial sense unless the vendor raises the price of the parts and the company is willing to absorb that cost.

How a company executes the machining processes used ultimately determines the product. Garbage in, garbage out. Dandy in, dandy out.