I’ve been trying to determine who makes the receiver, BCG, and barrel used on the 300 BLK uppers sold by AAC. I haven’t had any luck searching the forums, and AAC only specifies that the handguard is a KAC URX. They do state that the BCG is a full auto unit, but no mention of brand or specs.
Anybody know who manufactures the components of AAC’s uppers?
AAC won’t tell you.
The parts are made by various companies to Robert’s specc’s and QC’d in-house at AAC.
Hey, I remember you from silencertalk forums. 
Are there any markings on the barrel at least to suggest a source? Especially with barrels, the sources and materials have been either disclosed or discovered for almost every builder’s products out there (the worthwhile ones, anyway). With Daniel Defense and Noveske 300 BLK barrels, you know exactly what you’re getting.
At $1000+ for an AAC upper, I would expect a top-quality barrel. All they say about it is that it’s made of 4150 steel with a nitrided finish (including the bore and chamber), with 1:7" twist and threaded 5/8-24.
The AAC barrels are only marked something like 300 AAC BLACKOUT and the twist.
Robert and AAC don’t want to disclose sources, which is their right. I know they have over time sourced barrels from a couple sources. But, by the time AAC uses/sells the barrel, they have been made using materials specc’d by Robert, have been finished according to Robert’s specc’s, and have been QC’d and tested according to his guidelines.
It is not Remington, Bushmaster, or DPMS (or any Freedom Group Company).
BCM is close-lipped about their sources, for example… DD is proud to give all the details since they make them (very well BTW) themselves.
All of the AAC 300 BLK guns I have used have been excellent.
As you say, you expect a top quality barrel in a $1000 upper, and you get that with their uppers. Durable, perfect threads, and accurate. And warrantied no matter what. I can’t find anything but positive reports from owners.
The materials and finish are disclosed, the source manufacturer is not.
The only option not included is Cold Hammer Forging, and if that is important to you, DD offers 300BLK barrels made by them this way.
Or, of course, go with a complete DD 300BLK upper, or Noveske if your OCD requires knowing the manufacturer of the barrel. That’s fair.
It may be their right not to disclose information about their components, but by the same token, wise consumers are skeptical of the quality of barrels used by the likes of Bushmaster, Olympic, DPMS and others who also exercise their right to keep the composition and processes used in the construction of their products secret. This is elementary common sense. Daniel Defense operates one of a handful of AGFM hammer forges in existence, and they certainly have every reason to advertise that fact. An FN CHF barrel is made on a similar machine, and are considered top quality as well. Quality button-rifled barrels are fine too, but most of the members of this site are informed enough to stick to those made of 11595E-certified steels.
So what does it say when a builder is tight-lipped about the origin of their barrels? I don’t buy into anyone’s products based on anything short of facts. But I guess that’s considered OCD by some… :rolleyes:
It doesn’t say anything other than they have chosen not to divulge the information for their own reasons.
I don’t know about you but I also consider user reviews as facts. Like JasonM, I have not found a negative review on the AAC uppers.
I wouldn’t say OCD but (to me) it’s a need to know information that isn’t 100% necessary to make a decision on a 300 BLK upper.
If you absolutely, 100% have to know where all of the components of your upper are made, the AAC is probably not for you. As JasonM has also stated, there are plenty of other manufacturers who produce 300 BLK uppers and do communicate where they get their components.
It seems to me that they are simply protecting the branding cachet of their rifles and uppers, which is hardly an unreasonable practice. Were they to divulge specific components and vendors, that would doubtless become the new focal point of some completely off-point discussions along the usual lines of “buiding the same thing for less,” etc. etc.
Do we know where Noveske sources all of their parts? Does it matter that Colt outsources many components? Is BCM manufacturing half of what goes into one of their rifles? Obviously, the questions are really just rhetorical because the quality and reputations of these companies are well known. I’m not sure why that would be considered normal for everyone else, but suspect on the part of AAC, unless it’s just because (a) they are new to the game, and (b) we’re just trying to establish that we aren’t getting AAC laser-engraved budget Bushmaster uppers with top-shelf pricing.
If that were really the underlying question (and it’s a good one) than it would probably make more sense to just posit “is an AAR upper a rebranded Bushmaster or Remington product?” Preliminary feedback suggests that it is not, though at this point, I would probably be more concerned about how the parts are being spec’ed and inspected than with their specific points of origin.
AC
No assemblers broadcast where the get parts from. Ask BCM who manufactures their barrels, uppers, BCGs, etc. Colt, Noveske, Etc.
And again, if you want to buy from a source that divulges everything like DD, go for it, they are awesome!
Robert put a ton of work into not only developing the round, but the guns with which to fire it. I was around a lot of this process and saw the development of the round, the current ammo, the AAC guns, barrels, etc. this was both internal at AAC and with very specialized MIL units- which have had no problems with AAC barrels. I would not hesitate to buy one personally.
And again, i can say definitively that Bushmaster/DPMS/Rem/Freedom is NOT making the bolts, barrels, BCGs, receiver, etc.
Do you care who made the starter in your Nissan? As long as it works every time who cares?
I have five ARs, the last one has a Stag lower with a PSA 300 blk upper, still being assembled by them, do I care the upper receiver is the same as being sold by Stag, BCM or DPMS? No, as long it works I could care. There seems to be only a few people who make the forgings for the uppers and lowers. Sure Colt can order them to their spec, but they are swinging a big bat as far as getting what they want.
Buy from a company that appeals to you and look it over very carefully, if something seems wrong get in touch with them and let them make it good.
Fair enough, I don’t absolutely need to know the source of every component of their upper. I didn’t mean to include every single part, just the big ticket items like barrel, BCG, and receiver. What’s important to me is not really the source, but dealing with a known quantity, and knowing the source is one way to that end. If it was a DD barrel, for instance, I would be pretty certain it’s going to follow their usual standards for materials and process, but I admit I can never be 100% certain even knowing the source. I like the manufacturer participation we saw with “the chart”, and we learn something as significant from those who elected not to participate as we do from those who supplied their specs. I guess there isn’t anyone asking AAC for those details about their 300 uppers. I do value positive feedback from knowledgeable people who have put this product through its paces, and I have not seen any mention of a single problem with their barrels or uppers so far, but then I haven’t seen that much feedback about them overall.
For my purposes, AAC has an advantage in the choices of barrel lengths - 9", 12.5", and 16". For some reason, DD only sells a 16" 300 BLK barrel. Noveske has a few different lengths, but only makes 300 barrels in stainless. AAC is really the only supplier that has what I’m looking for at this time. I don’t have any experience with barrels with a nitrided bore and chamber, so I’m not sure what to make of this.
If you go to 300blktalk.com there is some discussion with Robert answering a few questions.
Bolts are 158 Carpenter. They are HP tested, but not MPI’d(or do I have that wrong?) and Robert points out exactly why they do not MPI them(I think there is actually a thread here somewhere where he discusses this). I think he alluded that Remington possibly makes the bolts as they have a ton of carpenter steel and its very very hard to get ahold of and you have to buy a ridiculous amount to even get it.
The barrel’s I think he said they have 3 or 4 different manufacturers that they source from and that they require each manufacturer to have tooling that only runs their barrels.
Like has been said though, who really cares. If it runs and its backed by a great warranty like AAC has, I could care less who makes the parts. My 9" upper runs awesome although I only have about 100 rounds through it since I just got it.
It really doesn’t matter if they are made on Mars, by little green men. The company has specified what materials are used. So you either accept that and purchase what they offer or don’t.
You should hopefully be smart enough to know which companies are known to cut corners and use shit parts, and which ones don’t. In addition I am fairly confident that they will stand behind their uppers and rifles just like they have with other products.
If you are that concerned then piece together your own upper.
I am not sure people realize just how many parts Colt and HK contract for their rifles, or Porsche contracts for their cars.
We have fully defined drawings, and in the same way that it does not matter if your M16 comes form Colt or FN, it does not matter who makes AAC carriers. They have to meet all of the specs on the drawing or else it would be rejected, and many vendors no-quote because they cannot or don’t want to make the part to the tolerances specified (for example, they may fear too many rejections).
We track vendor performance for QC and meeting delivery dates, and change vendors that underperform. I would never list a vendor for several reasons - here are a few:
We change them when they underperform, and I don’t feel like notifying everyone that we changed.
People would assume that it was the same product as the other products that vendor makes for someone else, and that is not the case - just like the company called Foxconn who makes Apple Macbook Pros to Apple’s specs makes other devices for other companies to different specs - so it is only right to think of a Macbook as an Apple product, not a Foxconn product.
Other companies would make a beeline for that vendor and also want to use them, then use up capacity and/or claim their products were the same as ours but a lower price when the value in our product is the design and the specifications it is made to.
Here are some specifics about some of the parts:
The carriers have a Nickel Boron (Ni-B) UCT EXO coating that has a very high hardness and lower friction than either Chrome or Nickel Teflon. There is a base layer of high-phospherous Electroless Nickel which ensures the extreme corrosion protection absent from other Nickel Boron carriers that use a single, thinner layer. The base material is highly polished before coating to ensure the smoothest surface finish.
The carrier and cam pin dimensions are custom machined to account for the thicker coatings rather than the more common process of simply coating a conventional carrier with a thin layer.
The bolt is Carpenter 158®, phosphated, and shot-peened bolt to ensure precise dimensions with no concerns for hydrogen embrittlement in the critical lug area. A special green o-ring was tested to not bind even at -40 degrees F. The extractor spring made from premium ultra-strong (338,000 psi) wire - and a low fatigue design ensures the longest possible life. The extractor pin made from 300 ksi S2 tool steel - not the much lower strength S7 more commonly used.
There is a properly-staked carrier-key with a Permatex® gasket-seal compound ensures no gas leakage.
The barrels designs were done with similar care - and while we do contract someone to pull the button through the barel and profile them to spec, the steel is 4150 and the bore profile was designed by me - so it is made with AAC designed and owned tooling. So even if I said it was XX barrel company, people would incorrectly assume it was like their other barrels, which is not the case since they only use our tooling with our barrels. It is more reasonable to just say that AAC barrels are AAC barrels.
We take this up a notch from most smaller companies by not just buying parts by name, but in many cases (like I am sure Colt and HK does also) providing a complete drawing with all specs fully defined so that we can QC the parts received against the drawing and have the ability to reject the ones which don’t meet the spec. If one were to just buy a “bolt carrier” by name, then you can’t really be in a position to reject any unless they are obviously bad.
The drawing for the barrels, for example, say that the muzzle threads must be concentric to the bore, not the outside of the barrel. Perhaps that same company makes their own barrels but the drawing they use for their own barrels says the muzzle threads must be concentric to the outside. We list high tolerances on critical parts and that costs us more. Our bore tolerancing is tighter than SAAMI specs, and we have a spec on chamber surface finish. The bore and groove profiles were determined so that the bore cross-sectional area is at SAAMI min if the bore specs were manufactured to the minimum dimensions allowed per the drawing. So a lot of care was put into this - we don’t use the normal blanks of the companies we contract, and all of the barrel companies we contract have our same tooling.
Our rifles come standard with Geissele triggers.
In summary - any spring company can make our extractor spring. They just need to buy 338,000 psi wire and wind it to the specs on the drawing. But if I told you which spring company made it, people would say “Oh, that is just a XX spring spring” even if they normally use 193,000 psi wire for everyone else.
Any pin company can make our extractor pin, but ask them for a quote and they would say “We can only get S2 tool steel with a minimum 20,000 lb order from Carpenter.” Well, we use S2, while most others (not Colt) would just order an “AR extractor pin” and not specify the material, and they would probably get S7.
S2 Yield Strength = ~300ksi
S7 Yield Strength = ~220ksi
Thank you, rsilvers, for the very informative post. That level of detail is above and beyond what I expected, and I appreciate the explanation of why sources are guarded. I did initially think most parts would have been chosen and assembled, as opposed to made to your specs.
If we were just buying parts I would not be interested in working on them. I want to have the best - a rifle I want to own and be my favorite - and we designed these to be capable of winning military contracts. Rather than make a standard mil-spec M4 style rifle, I took the approach of doing it more like an Individual Carbine competition rifle - using the latest and best but without going too far as I am still conservative.
I’m sold. Been wanting to pick up a 9" AAC upper anyway.
AC
That’s good to hear, I can certainly appreciate the drive to work on compelling, state of the art engineering projects. I’m grateful for your time and effort.
Damn. I want some upper now too.
I have had my 9" AAC upper since midish July. Much of the reason I went with AAC is because I have basically been through all of this researching already and was impressed with the care(by all outward appearances) rsilvers took in spec’ing the rifles. The other is that I have long arms and wanted short barrel but extra handguard and the 8" URXIII seemed ideal, time will tell if that was the case.
The thing that finally pushed me over the edge was the green o-ring(rsilvers you may remember the thread on 300blktalk). About a year ago it seemed that there were a number of threads by different individuals all over the net on different boards all having extraction issues that were eventually traced to the o-ring supplied as an upgrade that was getting stiffer in the cold. It seems as though this was though of before hand with the AAC product.
FWIW compared to early uppers mine has a pinned gas block. I have no idea when the made the change but it would seem that newer uppers are like that instead of the original pressed and set-screwed.
I am going with an AAC 300 upper too, but haven’t decided between 9" and 12.5" yet.
I like the 9" in theory - with a ~7" long suppressor, it would total about 16", which is great for a suppressed carbine, as long as the very short barrel length doesn’t excessively reduce the performance or longevity of a suppressor compared to the 12.5" barrel. I also like the fact that the handguard ends right at the base of the FH/mount, so it’s close to a seamless transition from handguard to suppressor canister, similar to an integral setup. The partial-length rails on the URX III handguard that comes with the 9" upper are strange, though.
The 12.5" upper seems like the more conservative solution, though the obvious compromise is an overall barrel length near 20" with a ~7" long suppressor. There is also a much bigger gap between the forward end of the handguard and the suppressor canister with this setup, so there’s that potential for snags. I don’t have any background with the 300 BLK round, so it’s not clear to me how much of a difference there is in muzzle pressure between the 9" and 12.5" barrels, especially with subsonic loads. With 5.56mm, those few inches make a significant difference in pressure and baffle erosion, but I suspect the 300 subsonic wouldn’t produce nearly as steep a length-pressure curve. If it meant any improvement in the effectiveness or lifespan of the suppressor, I would definitely choose the 12.5" upper over the 9".
For a 300 suppressor, I’d like to wait for the SR7 to come out, but if that looks likely to be delayed way into next year, I guess the SDN6 would be my choice. The AAC uppers seem to be in short supply anyway, so it may take me some time to find one.