You know how it starts. I have a nice DD LW barrel with .625 GB that I was going to use for another project that went in different direction. So now I have this barrel and an A2 upper just sitting there.

First world problem.

Some Colt RO727s had the lightweight 14.5" 1/7 barrel.

I am also wondering this, since I have a Bushmaster pencil barreled A2 upper on the way. Any pics in the wild to back this up?

This,  I did not know.  I was just going to call it a cut down 6520.

I have one of JCROWL's pic's of his on the ugly blue couch but I don't know how to get it on here without hosting myself.

The Colt M16A2 carbine Model 723 has the lightweight 14.5" 1/7 barrel

The only pics I have been able to find of a 723 show an A1 upper, no A2's.

Yes the RO723 had either the A1 or A2 F/S upper, and either a pencil or 203 cut profile barrel. The RO727 was issued only with the A2 upper and the 203 cut barrel AFAIK.

RO727.

~Augee

My understanding was 723 utilized A1 upper only with lightweight profile barrel. The 727 utilized A1 or A2 upper and M4 203cut barrel.

The RO723 utilized both "A1" and "A2/FS" upper receiver designs, as well as both "stepped" .750 FSB barrels and "lightweight" .625 FSB barrels.

The RO727 appears to have very briefly used .625 FSB barrels, and exclusively used "A2" style upper receivers.  

The RO723 displayed a huge amount of variability throughout its production run.  

~Augee

I am the proud new caretaker of a number of these Air Force frankenguns. GUU-5/Ps have all sorts of strange and unusual configurations. M4 barrels and 14.5 lightweight barrels, A1 uppers and A2 uppers, aluminum or fiberlite buttstocks and LE buttstocks, A1 grips and A2 grips, 4pos buffer tubes and 2pos buffer tubes, skinny handguards and fatty handguards (and one carbine I have has one of each!). Now, the overwhelming majority are built on A1 lowers, which would normally necessitate a NoDak or retro lower... Fortunately for you I have a GUU-5/P built on a Balimoy lower, so you're gtg with a modern lower with the A2 reinforcements as well. The GUU cloning game is a wide open market I'm telling you!

We need more pics.

While using the word "standard" in reference to a GUU-5/P is probably a mistake, this is the closest to a "standard" A2 upper'd GUU-5/P I've seen (essentially an M4 with an A1 lower and a fixed A2 carry handle). Next time I'm in the arms room I'll try and get some more pictures of the variations. Like I said though, I have at least one (and possibly 2) GUUs sporting lightweight 14.5 barrels, so that's an acceptable derivative as well, as is almost any other combination of A1 and A2 parts.

Edit: Here's a "in the wild" example of an A2 upper with a lightweight barrel. While this one appears to sport an A1 lower (as do most other GUU-5/Ps) as I previously pointed out they are also known to have Balimoy replacement lowers, which have the A2 reinforcements.

Augee,

Do you have any reference pics of a 727 with a .625 barrel by chance?

The photograph I posted six posts up originally came from Autoweapons from a transferable they were selling some years back.  

Besides that, evidence is few and far between, but information on commercial/export carbines not used by the military tends to be extremely difficult to find.  For all we know, almost all of the ones in that configuration could have been sold to a Latin American police force, and even if they were photographs of them, it would be extremely difficult to track them down and recognize them.  

Colt does not seem to have kept terribly comprehensive configuration notes, either - the RO727 was an S-1-F M16A2 Carbine with A2 sights, a two position stock, and a 14.5" barrel.  Doesn't tell you which lower forging, which M16A2 Carbine barrel, which forward assist, stock, etc.  

A similar barrel configuration, with a lightweight barrel was also used on the RO720 (XM4) however, and the R/AR/LE6520 "Gov't Carbine" would, conceivably have been the semi-automatic, 16" barreled version of the RO720, much the same way the LE6920 is the semi-automatic, 16" barreled version of the RO920.

As has been pointed out, the GUU-5/Ps is an option as well, though IMHO, they don't necessarily "count," as they're not factory configurations, and the GUU-5/P has even more different potential variations than the M16A2 Carbine.

~Augee

Got it, thanks. That first pic did not show up for me originally, had to open it in a new tab.

I guess for now I will keep the 723 with the M4 cut and the 727 with the pencil then.

Same here.  Maybe this will work:

Huh, interesting.

Sorry about that, needless to say, it's always worked for me.  

~Augee

The 723s had A1 uppers with and without the brass deflector. No A2 uppers (A2 upper did not appear until the 727). It had a 14.5" 1:7 pencil barrel (like the 653) and a 14.5" 1:7 stepped barrel (M4 type profile for M203). The 723s were designated as A2s, but they were transitional carbines. They had some of the A2 features (pistol grip, FH, FSB, and later ones had A2 lowers), but they still utilized the A1 uppers.

Here are two 723s I built.

Early model without brass deflector and 14.7" 1:7 pencil barrel (with permanent A2 FH)





Later model with brass deflector and 14.5" 1:7 stepped barrel (with jam nut and permanent A2 FH)




Model 727s have an A2 upper with a 14.5" 1:7 stepped barrel. No 727s had pencil barrels. The Colt Commando (Model 733) did come with A1 and A2 uppers.

That's what I thought too, but look at the eleventh, ninth, and second posts above yours.  The RO727 was commercial, Colt didn't keep particularly detailed notes about commercial configurations sold, and, as Augee has pointed out, Colt would put together any combination a buyer wanted as long as they bought enough units.   There appears to be at least one photo of a RO727 that purportedly came from the factory with a .625" barrel. More Colt shenanigans (?)

I just bought one of those DD .625 barrels, though mine will go a slightly different direction.


My inspiration.

If you noticed, the upper on it is not original to the weapon. The lower is an original M16A2 lower, most likely from a 723. It is possible the lower could be from a 727, but the upper is not. Like I stated before, the 727 had a 14.5" 1:7 stepped barrel (M4 type profile for M203). Before I built my 727, I did my research.

From Wikipedia:

The United Arab Emirates (UAE) wished to purchase M16A2 carbines with the thicker M16A2 barrel, but still be able to mount the M203 grenade launcher. The M203 grenade launcher was designed for the thinner M16A1 barrel. A "step-cut" barrel was made, with a portion of the barrel thinned for the M203 mount. M16A2 carbines with A2 upper receivers and the step-cut barrel were designated Model 727. These are often called "Abu Dhabi" carbines, in reference to the UAE's capital. The U.S. military also purchased several of these carbines prior to the official adoption of the M4.

You replicated the (original, commercial/export "Abu Dhabi") RO727.  That's a long way from being able to say that every RO727 had the step-cut barrel throughout the model's production span.  In your research, you undoubtedly noticed that Colt shoehorned all kinds of configurations into existing model numbers when it suited their purposes and they would make a factory run of whatever you wanted if you bought just a few hundred of them.  For that reason, I wouldn't hang my hat on the shade of the anodizing.  Is it possible that every RO727 had a step-cut barrel?  Yep, especially since that's the only photo that I've seen of what was purported to be a lightweight barrel RO727....  but in many cases it's probably best not to think in terms of absolutes when it comes to Colt's commercial/export production.

What is the background on the one you show in your earlier post? Is that your personally owned weapon?

As Augee posted (tenth post up from this one), it' was from an Autoweapons sale thread / ad.  That's why I used the word "purported".

What makes you believe that the upper is not original?  The difference in the anodizing color?  A lot of Colt factory guns - particularly during that time period were mismatched, and in particular, there's a good bit of evidence to suggest that Colt "pre-finished" a large number of M16A2 lowers that they simply "pulled out of the bin" to fulfill commercial and export orders - it's a well known fact that quite a few M16A2s were delivered with SAFE, SEMI, BURST marked receivers, but with S-1-F FCGs from the factory, to the point where "AUTO" marked lowers bring a slight premium.  

Also, even if it was not original, what model would the upper receiver have come from?  The barrel is a 14.5" with the period correct peel washer, so it couldn't have come from a semi-automatic commercial model, the only other alternative is that not only is the upper receiver not correct to the lower receiver, but that the whole upper is a mix-and-match upper.

On the other hand, while the S/N is not visible, the "big button" forward assist does suggest, as one would expect, that this was an early upper.  

While I did not save the exact verbiage from Autoweapons' sales ad (it's no longer on their site, presumably sold) - I'm fairly certain that it was advertised as a factory MG, not a parts gun, if only because I too had not previously seen evidence of lightweight barrels on RO727s, though I had begun to suspect it, and I remember finding/seeing the advertisement and being surprised by it, and looking at both the photographs and advertisements carefully, but I do not remember noting any suggestion that it was a non-factory gun.  





http://www.autoweapons.com/photos11/jan/vk227m16.html

WRT to the UAE export guns, there's a lot of conflicting information about them out there, and it's not entirely certain that they were RO727s at all at this point - the UAE "Abu Dhabi" story for the development of the M16A2 Carbine has been passed around for so long, that it's long been accepted as gospel, with various model numbers, including the RO723, RO727, RO725A, etc. have been attached to it.

The fact, however, is that the RO723 seems to almost certain predate the UAE order, and given the circumstances, it seems almost inevitable that Colt would have created a carbine version using a 14.5" barrel and A2 upper receiver, regardless of who ordered it "first."

Moreover, the RO723/7's heavier barrel with the M203 clearance cut appears to have been originally conceived of for the RO720/XM4 program, which began in the early-80s, and the timeline and documentation seems to suggest that the 7xx series .750 barrel may have been "adopted" for commercial/export production after the military had settled on which of the [at least] three barrel profiles they were considering for the XM4.  

Also, to suggest that the RO723 was not "fully" an M16A2 Carbine suggests a misunderstanding of what "M16A2" really meant to Colt as opposed to what it meant to the military -

The C7, for example, was not a "transitional" rifle - it was an M16A2 that happened to have "field sights," or "A1 sights" as they're commonly called - however, per Colt, the C7 upper, and other uppers with case deflectors were A2 uppers - the upper receiver used on C7s and late-RO723s was simply an "A2 upper with field sights."  

Now, early RO723s did use some "true" A1 uppers, without case deflectors - but the M16A2 was most specifically typified by the use of a 1/7 barrel, square front sight post, timed A2 compensator, and DuPont Zytel pistol grip with the finger shelf, all of which were features heavily advertised by Colt as the M16A2's "improvements," and consistent throughout commercial/export M16A2 production, regardless of whatever else might have been harder to pin down - to include the customer chosen sight configuration.  

~Augee

Interesting discussion here: http://www.ar15.com/archive/topic.html?b=3&f=123&t=406917

The closest thing with an A2 upper and a pencil will be the Colt 6520.



Augee, I have found no conclusive evidence that the RO727 came with a pencil barrel. There may have been retrofits done by some armorers, but there is no place that I have been able to find that documents the 727 with a 14.5" lightweight .625 barrel. If you have a link to prove they did, I would like to see it. I always like to expand my knowledge.

I never really saw many pics of Task Force Ranger before. I see in that one pic of Matt Eversman, he had a carbine in that pic and his character in the movie (as well as many of the Rangers) had a full length A2 rifle.

Interesting.

IIRC, quite a few members of TF Ranger had shorter-barreled weapons; the movie's producers gave all the Rangers M16A2s and the Delta/SOF CAR-15s so there'd be another immediate, obvious on-screen difference between the more "regular soldier" Rangers and the "high-speed" Delta/PJ/etc.

In the movie, Capt. Steele (who was a ranger) had a carbine.  I think it was a 11.5"er.  So maybe not ALL the Rangers.  Plus a lot of the Delta guys had 727's.  Except Sanderson, I think.  

But whatever, it was just a movie.  

I believe that in the movie their medic had what looked like a 10.5 A2 carbine.



Posted Via AR15.Com Mobile