WEAPONS OF THE WORLD: XM-8 Melts During Tests

StrategyPage.com ^ | April 14, 2004

[John Jorsett]

The U.S. Army has asked Congress for an extra $26 million to buy 7,000 XM-8 rifles next year. These weapons would be used to equip to infantry brigades and thus give the rifle a wide scale test. The money requested would also pay for the staff needed to monitor the testing. The rifle has already undergone thousands of hours of user testing and there have been some recommendations, all minor. The buttons on the sight are to be rearranged, to make the sight easier to use. There were also complaints about battery life for the sight, and a new battery is being obtained that will boost battery life from 200 to 400 hours. A more serious problem arose when the hand guard began to melt when several hundred rounds were fired in a few minutes. It was expected that the barrel would get very hot in these situations, but the heat resistant hand guard material was thought capable of dealing with that. So now a new hand guard will be needed, with more heat shielding. This will add some weight to the weapon, which is now 6.4 pounds. The designers are trying to get the weight down to 5.7 pounds. The issue of changing the caliber from 5.56mm to 6.8mm is still taking place in the background, with there not even being official recognition that there are 6.8mm version of the XM-8 being tested. There is a bit of competition among combat divisions to be the first to get the rifles for the 2005 test, with many officers lobbying to get one of their divisions brigades selected.

[hang 'em]

[knarf]

XM8 variants, from top: XM8 with XM320 40mm grenade launcher; XM8 Compact / PDW; XM8 Sharpshooter; XM8 Squad Automatic (drawing from H-K USA booklet)

Caliber: 5.56x45 mm NATO
Action: Gas operated, rotating bolt
Overall length: 838 mm in basic configuration, butt extended
Barrel length: 318 mm in basic configuration; also 229 mm in Compact and 508 mm in Sharpshooter and SAW versions
Weight: 2.659 kg empty in basic configuration
Rate of fire: ~ 750 rounds per minute
Magazine capacity: 30 rounds (STANAG) or 100-rounds double drum in Automatic Rifle/SAW role

The development of the XM8 Lightweight Assault Rifle was initiated by US Army in the 2002, when contract was issued to the Alliant Techsystems Co of USA to study possibilities of development of kinetic energy part of the XM29 OICW weapon into separate lightweight assault rifle, which could, in the case of success, replace the aging M16A2 rifles and M4A1 carbines in US military service. XM8 is being developed by the Heckler-Koch USA, a subsidiary of famous German Heckler-Koch company. According to the present plans, the XM8 should enter full production circa 2005, if not earlier, several years before the XM29 OICW. The XM8 (M8 after its official adoption) should become a standard next generation US forces assault rifle. It will fire all standard 5.56mm NATO ammunition, and, to further decrease the load on the future infantrymen, a new type of 5.56mm ammunition is now being developed. This new ammunition will have composite cases, with brass bases and polymer walls, which will reduce weight of the complete ammunition, while maintaining compatibility with all 5.56mm NATO weapons. Along with 20% weight reduction in the XM8 (compared to the current issue M4A1 carbine), this will be a welcome move for any infantryman, already overloaded by protective, communications and other battle equipment.

The XM8 will be almost similar to the "KE" (kinetic energy) part of the XM29 OICW system, being different mostly in having a telescoped plastic buttstock of adjustable length, and a detachable carrying handle with the sight rail.

As of November, 2003, first 30 prototypes of XM8 were delivered to US Army for initial testing, with further 100+ prototypes scheduled to enter tests early in 2004.

Technical description.
The XM8 is a derivative of the Heckler-Koch G36 assault rifle, and thus it is almost similar to that rifle in design and functioning. XM8 features a short piston stroke, gas operated action, with rotating bolt locking. Barrels are quick detachable, and planned to be available in several sizes, ranging from 229 mm (9.5 inch) for Compact/PDW version, 318mm (12.5 inch) in Basic version, and two 508mm (20in) barrels, one for Sharpshooter/Sniper version, and heavier one (along with bipod) for Squad Automatic Rifle role. The entire construction is modular and built around the polymer receiver with bolt group; Magazine housings could be easily swapped for compatibility with various types of magazines; various buttstocks could be installed in a second for various roles (standard buttstock is a telescoped 5 position adjustable one). Top of the receiver is fitted with proprietary sight rail, which can accept illuminated red-dot (collimator) sight, or any other type of sighting equipment. Detachable forend will be available in various sizes, and could be replaced with XM320 40mm grenade launcher (the improved HK AG36).

Ambidextrous fire controls are mounted on the trigger unit, integral with pistol grip and triggerguard, and in basic configuration are planned to deliver single shots and full auto fire. The G36-type ambidextrous charging handle is located at the top of the receiver, below the removable carrying handle.

--

[Dr. Faust]

Forget the minor revisions. My only question is will it improve a grunt's chance of icing a rughead?

Reach out and touch someone!

[aft_lizard]

Too bad its the Germans making this rifle, why couldnt a American company make it

[Blood of Tyrants]

You would think that this particular problem would have been discovered in the early stages of testing. However, switching from 6.8 mm to 5.56mm to save a few ouncues is a big mistake.

[45Auto]

Article on the 6.8 mm SPC

6.8 Remington SPC

[AdamSelene235]

Barrel length: 318 mm in basic configuration;

12.5" for a 223.....what a joke...

[Caipirabob]

You would think that this particular problem would have been discovered in the early stages of testing.

HECK YES!

Even firing my AK variant in rapid single-shots the darn thing heats up enough to burn the skin off you. The Palmetto bugs don't like their end of it either.

Seriously, if they've even run it through basic trials something like this should have come up already. I'm beginning to fear for the safety of our soldiers already. Last thing they need in a life or death combat situation is a gun that surrenders like a Frenchman while they're still fighting.

[45Auto]

Barrett M468 chambered in 6.8 Remington SPC

[muleskinner]

its the Germans making this rifle, why couldnt a American company make it?

'Cuz the Krauts live for stuff like this.

[aft_lizard]

http://www.hk-usa.com/pages/military-le/mil-leimages/xm8_rightmed.jpg

[aft_lizard]

http://www.hk-usa.com/pages/military-le/mil-leimages/xm8_rightmed.jpg

[aft_lizard]

http://www.hk-usa.com/pages/military-le/mil-leimages/xm8apgsold1popup.jpg

[aft_lizard]

sorry for the double post earlier
Here is a link to the XM-8 companion the XM-320 grenade launcher
http://www.armytimes.com/story.php?s=1-292925-xm8_grenade.php

[shadowman99]

Misleadig title. Only the hand guard melts, and they already have a design solution underway.

[Future Snake Eater]

Yeah, that title was just a tad sensationalist.

[Robert A Cook PE]

90-95% of all shooting, in all wars since the mid-1800's, has been a t very, very close-range.

The "myth" of a sharpshooter aiming and firing at individual targets that he can specifically see and aim at (except, of course, specialized sharpshooters and snipers!) just doesn't happen in real combat.

A short barrel and a small caliber bullet is adequate, just as Stoner originally designed in the AR-15 before the Army firearms officials screwed it by re-designing it as the first versions of the M-16.

[Xenalyte]

Hey, isn't that what happened to Eaker's gun or something?

[Monty22]

The barrel on this thing is too short to launch the .223 even at a 3000fps muzzle speed. In short, it's just a fast .22 long rifle at this speed.

You really need 3000 fps to produce hydrostatic shock on impact, which makes it an effective round.