M-4 GAU-5?

[FuturePara]

Okay so I was flipping through that new book about PJ's in Afghanistan and the author was talking about something called the GAU-5 Rifle. There was a picture of a PJ with an M4A1, but he called it a GAU-5. What exactly is this, and is it a common term? Or is this just something the author made up, or is it just what the PJ's call their M4's?

[USAF G]

GAU-5 is what the Air Force calls it's short M16s. I hesitate to call them M-4s, since most of them began their lives as M16s or Commandos(which were also called GAUs). They now have the same features as the other service's M-4s. Cheers, G

[REMOV]

There was a picture of a PJ with an M4A1, but he called it a GAU-5. What exactly is this, and is it a common term?
This is name for XM-177E1 and XM-177E2 in USAF. The GAU-5/A is a XM-177E1 without the forward assist (10" barrel). GAU-5/A/A is a XM-177E2 without the forward assist (11,5" barrel) or M649 M16A1 Carbine (14" barrel).

A 1984 memo directed all USAF GAU-5/A's and GAU-5A/A's to have the muzzle compensator removed. And replaced with the M-16A1 muzzle compensator. Some were modified, some were not.

The USAF made a quick internal fix to the 1/12~1/7 twist on most of the GAU series carbines. The CATMS (Combat Arms Training & Maintance Specialist) replaced the the 10 & 11.5 inch barrels. Installing a 14.5 inch barrel with the M-16A1 muzzle compensator. All the carbines I have seen of this configuration were stamped GAU-5/P. I could not find out the acronym breakdown for this new designation. These are still being used, although they are slowly being replaced with the M-4/4A1 carbines.

The best way to distinguish (in photos) original XM-177E1 & XM-177E2 carbines is, they DO NOT have bayonet studs! Any carbine labeled this is incorrect. Same holds true for the GAU-5/A and GAU-5/A/A. No bayonet lugs!
Source: http://feistyrooster.com/XM177/

GAU-5/A/A
http://dspace.dial.pipex.com/town/walk/gen55/dgca/images/M4/GAU-5A.jpg

[thatguy96]

If you're sure its an M4 then its a misnomer. The US Air Force designated their version of the XM177E1 (Colt Model 610) the GAU-5/A and their version of the E2 (Colt Model 649) GAU-5/A/A. I would think it weird for the US Air Force to go backwards in their designations, so if its an M4 then its probably not a GAU-5, or perhaps the Air Force went one step further, designated it GAU-5/A/A/A and the book's editors felt no need for that.

Further note, you said that this was a photo from the current operations in Afghanistan? I believe that all XM177's were removed from service by, at the latest, the 1970's, meaning that unless M4's are designated GAU-5 as well, this book is wrong.

-edit-

It would appear from the information provided above that the Air Force is in possession of a bunch of hodge-podge pre-M4 carbines as well, further adding to the confusion.

Duncan Long, in his book The AR-15/M16 Sourcebook says that as they left the factory, the carbines specifically for the USAF are thus:

Colt Model 610: "Commando, U.S. Air Force XM177, without forward assist, 10-inch barrel, no bayonet lug, low-noise muzzle brake with flash hider, round and ribbed handgaurd. Marked 'Colt AR-15'"

Colt Model 649: "Commando with 11.5-inch barrel, no forward assist, large flash hider, telescoping stock, M16A1 receiver, Marked 'Colt M16' (US Air Force)"

The information above would also provide insight as to why biggerhammer.net claims that the Model 649 had a 14" barrel rather than Duncan Long's claim of 11.5". I have seen pictures of what appear to be A1 carbines without forward assists in the hands of USAF operators, and now that appears to also be explained.

I think the last point I will say on this subject is that given the modularity of the AR-15/M16 system and the constant modifications by various entities (an example of which can be seen right here with the AF), that very few weapons like this (carbines and even shorter rifles, used by special force or similar groups) are ever to their "box specs" anymore, and one should be wary of the captions of photos of spec ops operators especially, that contain very specific type references to equipment used.

[D.E. Watters]

The USAF’s GAU-5 series started with the original XM177, and consists of four variants differing primarily in barrel length. The models are the GAU-5A, GAU-5A/A, GAU-5A/B, and GAU-5P. Only the GAU-5A/B possessed a forward assist; they appear to be surplus XM177E2 absorbed into USAF inventory.

The GAU-5P is the longest, equipped with a 14.5" barrel. Many of the older weapons were eventually converted to this variant when the individual weapon required rebarreling.

Several years back, the GAU-5 still in USAF service were eventually upgraded with a 14.5" M4-configuration barrel using a 1-7" twist. These upgraded models were redesignated GUU-5P.

As of November 2002, the USAF began to procure flat-top M4 fitted with the M68 CCO to replace their older M16/M16A2 rifles and GAU-5/GUU-5 carbines.

[thatguy96]

No offense, but would it have killed the services to have common designations?

[drums]

Okay so I was flipping through that new book about PJ's in Afghanistan

What's the book? I just did a quick search on Amazon and didn't come up with anything all that recent....

[thatguy96]

I just remembered someone had shown me this (http://www.af.mil/media/photodb/photos/030801-F-0000W-003.jpg) pic, which is straight from the USAF website (although the operators arm patch makes life slightly confusing...), and if you look at the weapon, it appears to be exactly what we're talking about. A weapon with an antiquated reciever group, M4 profile barrel and a rail handgaurd, creating a weapon which isn't an M4, isn't an A1 carbine, and isn't a "Commando" in the generally accepted usage of that term.

[Ekie]

Being that this is a "photo" web site, here ya go:

http://www.af.mil/media/photodb/photos/030801-F-0000W-003.jpg

OPERATION ENDURING FREEDOM -- Capt. Danny Stout, an air liaison officer deployed with the Army's 2-505 Parachute Infantry Regiment of the 82nd Airborne Division, takes a much-needed break during a classified mission in the mountains of Afghanistan. Stout, a B-52 Stratofortress pilot serving a two-year tour with the Army, keeps his eyes in the skies for hours at a time to control coalition aircraft on close-air support missions. (U.S. Air Force photo by 2nd Lt. Rebecca Garland)"

[Ekie]

Oh yeah, sorry, don't have any bigger pictures, hehe.

[FuturePara]

The book about USAF PJ's in Afghanistan is called "None Braver: Air Force Pararescuemen in the War on Terrorism." I'm gonna go out and get it today. I need something new to read.

[REMOV]

The USAF’s GAU-5 series started with the original XM177, and consists of four variants differing primarily in barrel length. The models are the GAU-5A, GAU-5A/A, GAU-5A/B, and GAU-5P. Only the GAU-5A/B possessed a forward assist; they appear to be surplus XM177E2 absorbed into USAF inventory.Hmm... do you have any photos of those rifles? Or - to be exact - more photos than posted here untill now? (also GUU-5P).

TIA

[D.E. Watters]

Hmm... do you have any photos of those rifles? Or - to be exact - more photos than posted here untill now? (also GUU-5P).


Sorry, I don't have any photos to submit.

[haze99]

No GAU-5 is not a misnomer, go over to the equipment and gear forum. Check into the M-16 Story post. I explain, the whole USAF GAU-5 issue.

This USAF Air Liasion Officer is with the 20th Air Support Operations Squadron. *It is aligned to the US Army's 10th Mountain Divison (Light)
He has a GUU-5/P carbine leaning next to his ruck. This weapon was originally a GAU-5A or GAU-5A/A, sub-machine gun. It was refurbished with a M-4, 14.5 inch, 1/7 rifling, stepped barrel. This ALO has replaced the original handguards with a KAC M-4 RIS. The GUU-5/P is slowly being replaced with the M-4 series carbine. (see M-16 Story)

[pettifogger]

You realize you're replying to a message posted over 14 months ago?

[Sepper]

Is it more common nowadays (in USAF or otherwise) to see A1 Style receivers with the forward assist or without the forward assist?

[pettifogger]

The GAU-5/A and GAU-5/A/A did not have forward assists. When they were upgraded to GUU-5/P, the barrel, not the upper receiver was replaced, so they still lack forward assists.

http://www.gun-world.net/USA/M16/CAR/usafsp_guu5p.jpg
http://www.gun-world.net/USA/M16/CAR/usaf_secu.jpg

Even now in Iraq, the USAF is still using those 40-year old carbines without forward assists.

http://www.af.mil/media/photodb/web/web_030909-F-6705C-065.jpg
http://www.gun-world.net/USA/M16/CAR/usaf_engineer.jpg

Outside of the USAF, M16A1 carbines will have forward assists. The USAF was the only major purchaser of carbines without forward assists.

The USAF does also have some Model 723 M16A2 carbines, which have forward assists and A1-style sights, but A2 case deflectors.
http://www.gun-world.net/USA/M16/CAR/guu5p_usafsp.jpg

And to show how non-standard the USAF is, here's a M4 with a commercial version SIR.
http://www.af.mil/media/photodb/web/040805-F-9995T-027.jpg

[REMOV]

Plus GUU-5P with M203.
http://img139.exs.cx/img139/4590/guu5pm2034yg.jpg

[fantassin]

The USAF uses some really old rifles too; when I was deployed with US troops some months ago, there was a USAF Sgt in an Intel cell who had an original AR15 with no forward assist, the old style muzzle brake and it was shiny new !

He had a non-stop flow of gun nuts in his office to handle that piece of 1960s vintage weaponry; I had never seen a real pre-Vietnam vintage AR15 and it was unbelievable to see it was still in "operational" service (even though the USAF guy was desk bound) 40 years after having been admitted.

[Hydro]

If you watch the film "HEAT", at the beginning during the heist on the armoured car, Robert De Niro's character Neil is toting a GAU-5/P.

[Sepper]

Anyone know if most of the barrels on the GAU-5s been replaced with the M4 203 mount style barrel? Or are they still predominantly the A1 style barrels?

[pettifogger]

Most of them have been replaced with the M4-profile 1/7 barrel, in order to fire the M855 round. The barrel conversion kit is is NSN# 1005-01-319-7111.

[MikeWilliamson]

So it's an old thread.

Last time I handled weapons for USAF (Last year), there were original M16s slicksides, but mostly converted to parkerized bolt carriers instead of hard chrome, for some unfathomably stupid reason. There were A1s built on M16 lowers, and A2s done with conversion kits and engraving pencils to scratch out "auto" and write "Burst" freehand. Some had straight sliprings, some had delta. Some M16s had A1 buttstocks and A2 handguards. There were GAUs with THREE position stocks, with 16" barrels, M4s with carbine stocks instead of M4 style, with A1 forward assist and sights, with A2, A3, and "M16A1" M203s without forward assist.

Pretty much none of it except a few early GAUs and some original M16s were factory; almost everything having had multiple generations of upgrades.

Short answer: any combination of Colt or contract parts you put together will be "Authentic" somewhere in the system.

I've even seen a photo of a PJ on ar15.com with his shorty handguards mounted sideways, cut around the gas tube. I presume it was to reduce thermal distortion on night vision.

[limacharlie]

The Gau-5a-a Was Still In Use In The Usaf As Of 1991. Also We Had Xm-177 Stamped On Some Of Them. Although They Looked Ragged, They Fired Just Fine. Large Flash Suppressor, And A Metal Telescoping Butt Stock, They Were First Designed As An Easier Weapon To Handle For Sp Canine Troops During Nam. The Slings Were Attched To The Top Of The Weapon So It Could Be Carried And Fired In The Strong Arm Only While The Handler Held His Leash In The Other. When He Made Contact He Would Fire The Weapon On Full Auto Strong Side And Lead The Bullets Up To His Target Then Release The Dog. Good Stuff. 4392 Spg/armorer

[thatguy96]

All I have to say for anyone going back to this thread is:
http://www.ar15.com/forums/topic.html?b=3&f=118&t=267251&page=1

and for those of you looking to be more involved on another level
http://groups.yahoo.com/group/1960sar15/

[MikeWilliamson]

That Guy: I found this link while searching those.:)

My unit's M4s just came back from Afghanistan. With/without foregrips, with/without rails, with/without optics, 4 or 6 position stocks, with/without side mounted sling swivels...take your pic. :)

[akmarksman]

If I remember right..the Army or Airforce SRT team..had some GUPS (not an m-4,not quite a M16)..and the M16A2 with a carryhandle scopemount,scope,D3ltA cheekrest on the stock and a bipod.

Wouldn't it make sense just to take the G-variants off their hands and hand them shiny new M4s?..All new manufacture..etc.

[MikeWilliamson]

Why waste money on a new weapon when the receiver or when the old one still works? As long as the pin holes are still tight, no problem.

[tacticalcity@yahoo.com]

While assigned to the 438th AMPF in the 1990's we were issued GAU-5s. Mine had never been fired before (aside from the factory test), and it took me a while to break it in. So the assumption that these were all parted from older weapons is incorrect. We cracked open the crate on these babies. There were no scratches, dings, or pits...and we were told they ordered them straight from the factory just for us. This was in 1992. I carried the rifle the entire time I served in this Flight. Unlike a lot of USAF units, this rifle was mine and mine alone. A lot of flights share rifles. We didn't. We were not allowed to modify the weapon in any way. No aftermarket sights, etc.

At this time, almost everyone in the USAF carried the full length M-16. This was the first time I had ever seen the shorter CARBINE version, but then I wasn't much of a gun buff at the time. My point being, except for Spec Ops, we were the only ones on base using them. When we deployed (which was the whole point of our unit)...the other services had simular rifles. However, we only deployed with Special Operations teams. So this doesn't mean regular infantry had them in abundance.

These days, the M-4 and variations are extremely common in the armed services. You see them everywhere. This wasn't always the case.

The most notable difference in functionality between our rifles and those carried by others is that the GAU-5s we were issued came with FULL-AUTO not just the short burst almost all the other M-16 variants at the time came in. If necessary, you could empty an entire magazine on a single trigger pull. Of course, we were trained not to do so except in the most extreme circumstances.

I would love to tell you exact barrel length but it has been almost 16 years, and I have been issued and owned too many rifles since then. It was 10.5", 11.5 or 14.5" but I'm not sure which. It had the M-4 style barrel. They all came with the forged carry handle type upper receiver. If anybody in the USAF had flat top rifles back then, its news to me.

Then again, almost no one in the USAF knows that units like ours existed, so it wouldn't surprise me to learn that there was a unit out there somewhere carrying them, doing something I had no idea the USAF did.

That's the thing about the USAF. They’re not into to macho self promotion. They talk about the planes and the bombs, but not their specialized combat units. They want you to think the only ones who see combat are the pilots.

This is not true. In addition to 3 separate Special Operations career fields, there are all kinds of specialized units that take part in the war on the ground. One day you're working in a control tower or pushing pallets, the next day your part of a mobile aerial port serving in a combat zone. These units never get any press...but they exist. And almost all of the members in these specialized Squadrons and Flights carry the GAU-5.

[Slater]

In the USAF in the 1980's we had M16's (stamped "AR-15") with the old three prong flash suppressor and no forward assist. These were stored in the WSA and never saw the light of day except for exercises and as needed for cetain duties. They were some of the newest "old" M16's I'd ever seen.

[The Starfox Kid]

Wow, did this thread really need too be brought up from the grave,

[Aldo Penniconi]

The "GAU-5" designation makes it sound like somthing else, More like an Aircraft mounted weapon.

[futurepilot2004]

The "GAU-5" designation makes it sound like somthing else, More like an Aircraft mounted weapon.

a two year old thread just to say that???

[James]

Since it's back, there's a lot of interesting info at:

www.retroblackrifle.com

[Vince S]

I'll venture on saying it's one of your favorite site these days James? p-)