Deployed MEU's getting M-4 Carbine?

[ChuckMK23]

Looks like forward deployed units are seeing a lot more of the M-4 with RIS and PEQ-2.

Lots of other images of Marines carrying same weapon...

http://www.usmc.mil/marinelink/image1.nsf/Lookup/20061452442?opendocument

 

[TheBubba]

I like'em... had a chance to fire one on a combat course a few years ago. T'was a good experience. Found out I'm not as good a shot as I thought I was... have since corrected that deficiency.

Couple Q's about the carbine:

1. Was told that the range/accuracy isn't as good as the M-16. This makes sence due to the shorter barrel, but is it true? I distrust the source b/c he's blown smoke out his ass about other stuff.

2. Read somewhere that the M-4 was designed to the specifications needed by sec-ops/spec-war units. Any background info on this?

-Bubba

 

[Blutonski816]

You're thinking of the SOPMOD M4A1... yeah that was originally for the special ops community

And about the acuracy... I remember someone mentioning how the use of the wrong round is producing poor ballistincs for the 5.56 rounds...
Rounds meant for the M16 are being used in the M4, but without enough barrel length, the muzzle velocity is much less than needed....
there is a round meant for use in the M4 that produces a much more satisfactory muzzle velocity... don't remember specifics.. I'm sure someone will chime in and fill in the rest....

 

[ChuckMK23]

...and the Marine in the picture had a SOPMOD'd M-4 - note RIS handguard and PEQ-2 illuminator/designator on top rail - and EOTECH HoloSight

 

[TheBubba]

Cool... thanks.

I fired the M-4 with the ACOG 4x scope... don't know how it stacks up against other scopers in military use, but I like it alot... and so did the SEALs that were running the course...

 

[Blutonski816]

The ACOG is really expensive a lot of that due to the fact that you don't have to deal with replacing any batteries, like a lot of modern Red Dot sights... which are much cheaper than an ACOG, wich is why a lot of operators will have Aimpoints on their Weapons...



It's a sort of Pro/Con type of thing (aimpoint approx $360 vs. ACOG approx $700)... If I could get my hands on and ACOG... hell yeah....

 

[squeeze]

The range is fine... just as good as an M-16... *WITH THE RIGHT AMMO* The problem is, the GI M-4s have a 1:7 barrel twist that is insufficient for stabilizing the current 62gr M855 load in a 16" barrel (fine with 55gr). It works fine in the 20" M-16 barrel though. The 1:7 was originally designed for the 62gr bullet in a 20" barrel (55gr was designed for the 1:12 M16A1), but when the US started using the M249, they found it didn't function properly with the 55gr, so the 62gr replaced it. With standardization being king and all.... all we have is the 62gr now. There are a couple newer bullets being tested that work better in the 16" 1:7 barrel, but I don't believe they are in general use yet.

I have what is essentially an M4. A 16" AR with the M4 barrel, and a 4x32 ACOG. The big difference between mine and a real M4 is the 1:9 barrel twist. The tighter twist is sufficient to stabilize a 62gr round in a 16" barrel, so I can achieve the same accuracy (actually a bit better) than your run of the mill M-16.

edit: The ACOG is expensive because it is fucking QUALITY. It is one of the finest fit/finish optics I've ever used. But yes, the damn thing cost almost as much as my rifle (the world's most expensive AR project)

 

[Blutonski816]

I have what is essentially an M4. A 16" AR with the M4 barrel, and a 4x32 ACOG. The big difference between mine and a real M4 is the 1:9 barrel twist. The tighter twist is sufficient to stabilize a 62gr round in a 16" barrel, so I can achieve the same accuracy (actually a bit better) than your run of the mill M-16.

edit: The ACOG is expensive because it is fucking QUALITY. It is one of the finest fit/finish optics I've ever used. But yes, the damn thing cost almost as much as my rifle (the world's most expensive AR project)

Living proof that there isn't a single Marine who doesn't have a weapon that I don't envy....

 

[A4sForever]

Ditto with Squeeze's post ... I don't usually subscribe to Wikipedia for a variety of reasons --- having said that, check out these two links for a relatively good treatise and history on the Colt "shorties" , ie, the Commando or XM177 type and the M4 Carbines .....

M4 Carbine


http://en.wikipedia.org/wiki/Colt_M4

Vietnam-era XM177 (a.k.a. Colt "Commando")

http://en.wikipedia.org/wiki/XM177

 

[xmid]

Real M-4's actually have a 14.5 inch barrel but I dont want to seem nit picky. I read alot about the testing of the prototypes and they found out that 14.5 inches was actually the shortest barrel with the least amount of energy/accuracy lost. I don't remember the exact statistics, but I wanna say the 14.5 inch barrel only losses 300 fps over the 20 incher. The army has had some problems with the barrels cracking from hard impacts, like landing under a parachute. The M-4's barrel is actually contoured to be slimmer under the hand guards so that it dissapates (sp?) heat better. With the m203 slung under it it creates stress fractures on the contact points. Rumor has it that the Marine Corps got wind of that and didnt want to deal with the expense of buying them and then worry about replacing barrels when they where thrown around.

 

[xmid]

The SEALs actually just bought a bunch of M-4's from Barrett, the guys that build the .50 cal sniper rifles. Barrett is making an "improved" m-4 that is chambered in a heavier caliber. I think the new round is around 115gr or 120, its said to have comparable ballistics to a 7.62, but obviously in a much smaller/lighter package.

 

[squeeze]

Real M-4's actually have a 14.5 inch barrel but I dont want to seem nit picky. I read alot about the testing of the prototypes and they found out that 14.5 inches was actually the shortest barrel with the least amount of energy/accuracy lost. I don't remember the exact statistics, but I wanna say the 14.5 inch barrel only losses 300 fps over the 20 incher. The army has had some problems with the barrels cracking from hard impacts, like landing under a parachute. The M-4's barrel is actually contoured to be slimmer under the hand guards so that it dissapates (sp?) heat better. With the m203 slung under it it creates stress fractures on the contact points. Rumor has it that the Marine Corps got wind of that and didnt want to deal with the expense of buying them and then worry about replacing barrels when they where thrown around.

Ok yes, the barrel is technically 14.5" with a permanently attached 1.5" flash hider, so most people refer to it as a 16" barrel.

And acutally, both the M16 and M4 have the same barrel profile from the gas block back. A Govt-profile barrel tapers from .675" to .605" under handguards, then .715" from the front sight to the muzzle. It's only forward of the FS/GB that the M4 is different where it has the .601" diam for the M203 mount. The newer M4A1's have a slightly heavier barrel under the handguards but it's almost negligible (4oz). But you're correct in the ~300fps drop difference.

Edit:
The Barrett-built M4 you're referring to is the 6.8SPC, which, while used in some VERY limited cases, will never make it 'bigtime' in the military. Too cost prohibitive.

 

[A4sForever]

The SEALs actually just bought a bunch of M-4's from Barrett, the guys that build the .50 cal sniper rifles. Barrett is making an "improved" m-4 that is chambered in a heavier caliber. I think the new round is around 115gr or 120, its said to have comparable ballistics to a 7.62, but obviously in a much smaller/lighter package.

Are you referring to this (?): posted 3-31-2005 on AW's .......

Barrett M468: Upper receiver M468/M16 proposed conversion kit

The 6.8mm is the next best thing since sliced bread to come along in the field of military cartridges for shoulder weapons in a long time. It was hoped it would overcome any residual M-16/M-4 maintenance and reliability issues, overheating (especially in the M-4s), and the less than stellar stopping power and penetrating capabilities of the Remington .223 (5.56mm NATO) cartridge. I personally think the 5.56mm NATO was a HUGE mistake and one can only speculate on how many U.S. casualties have resulted from using a less than man-stopping cartridge since its inception. We need a true "Assault rifle" cartridge --- not a "varmint cartridge" for the troops.

The biggest problem with its adoption, as I see it, are the millions and millions of 5.56 NATO cartridges already purchased and in the system. Let the bean-counters figure out a way to sell them or eat them and maybe we'll get a replacement. There is significant interest withing the military establishment to return to a .45 ACP sidearm --- BUT: I think the real reason we are still issuing a 9mm instead of a .45 ACP is too many 9mm's in the system --- but that's just me. By the way ... I fired my XD .40 S&W yesterday at the range --- and I think a 9mm has more recoil !!! Maybe I shall stick with the .45 ACP ??

The good news is that you can buy a conversion top end from Barrett --- bring along $1590 for the conversion or $2700 for the complete rifle.

Interestingly, the 6.8mm is also .270 caliber. I'm not going to look it up tonight, but I believe that was one of the cartridge options being considered by the Army when the M-1 Garand was undergoing trials in the '30's. What do you think was the final clincher in staying with the .30-06??? That's right --- so many 30-06 cartridges already in the system .... so the more things change, huh ..... ?????

 

[xmid]

I have heard people say that they brought a personal side arm over to the sand box with them. For instance a police officer I know went with the guard and he took a .45 in addition to his issued side arm. Could a marine buy an m-4 upper with his own money and install it on his issued m-16 prior to deployment? Or could an entire platoon or whatever get together and all purchase said uppers? I for one would rather have something a little smaller than the 20 incher. -RIFLE 20 Inch RIFLE!!! before someone makes a joke

 

[Gatordev]

One problem is getting your hands on the ammo you need for your personal weapon. Unless you're part of some gucci SpecOps group, your unit only gets the ammo that's been allocated to them. On the Navy side, unless you're a SEAL or maybe EOD, getting your hands on .45 ammo would be pretty hard, at least in my experience.