SCAR vs. M4 vs. HK416 vs. XM8 Dust Tests Released - M4 Loses Badly

[GunTech]

HK really wants that contract.

The Galil is a great rifle if you want something heavy, moderately accurate and with no provision for mounting accessories. The latter can be fixed, of course, but I'm not sure it's really a solution, and I love mine.

 

[Slater]

M4 improvements?:


http://www.armytimes.com/news/2007/12/army_m4_hearing_071217w/

 

[Grayrider]

I must get a railed gas tube for my Galil. Other than that I too am quite happy with it. Of course my Arsenal 106FR is also quite reliable and piston driven.



John

 

[Onmilo]

The report doesn't state how the test shots were fired.
Full auto? Burst Fire? Semi auto?
The glorified G36 outperformed everything else and the SCAR outpreformed the fabled 416!!??

There seems to be a blending of the tests, some are listed as winter, some are listed as summer.

Nothing in the report lists the dispersion of the shots fired.

It's wonderful, the rifle can go bang when it is dusty but if the bullets are hitting six feet to the left of the aiming point the test proves exactly what?

It is my understanding that Delta chose the 416 because it IS more reliable when subjected to extremes while not being given the luxery of regular cleaning and maintenance shcedules, not because it works better when dusty.
Something doesn't feel right here.

 

[strangelittleman]

I can somewhat under stand the XM-8 and the SCAR doing a bit better due to there being quite a bit more open space between the bolt carrier group and the upper reciever allowing the dust/dirt to fall away and not get as bound up between the bolt carrier group and inside of the upper reciever, that only makes sense. Combine that with a good magazine design and you've got potential for very reliable operation in extreme environments.

I honestly think that since the M4 type rifles have such tight tolerances in the relationship between the bolt carrier group and the upper receiver, that is where the "problems" lie in regards to reliability in extreme environments, that along with bad magazines make for a multitude of problems. I've said a thousand times,"bad magazines are the root of all evil." I can't help but think the M4 was sadddled w/ poor mags during this test. I feel that if the SCAR,M4,HK416 all had the same mags (all have the USGI or HK-HR) things would have been a bit more representative.
I also don't see how big an improvement the 416 is over the M4, when they both have essentially the same close tolerances between the bolt carriergroup and upper receiver, sure the 416 has the gas piston, which is most probably a great improvement when comparing the shorter 10.5" bbl versions of the AR w/ 416, but in the longer barrel versions not as much of an improvement. I know the introduction of the hot gases into the upper reciever can cause the lube to dry up, but this would not be such an issue if it weren't for the tight tolerances.
Extreme enviroments require a looser relationship between the major moving parts and the interior of the upper reciever, pure and simple. Look at the FN FAL, when the Brits first adopted it in the late 50's/ early 60's, they found that it had too close interior tolerances between the bolt carrier and upper receiver, so they had great big zig-zag channels milled into the bolt carriers of their SLRs, once this was done there was somewhere for the sand/dirt to go rather than binding up the bolt carrier in the upper.
I think that if a minimal amount of R&D was carried out to "recontour" the exterior of the AR's bolt carrier group to allow more space between the upper receiver and it, without sacrificing the needed bolt carrier weight and still allowing sufficient contact w/ the upper receiver to maintain good lock-up and to retain good accuracy, a good rifle would be made even better.

 

[Slamfire]

Folks who don’t like the type of test should go to DoDiss http://assist.daps.dla.mil/quicksearch/ and type in 810 in document number and look at Mil Std 810F.

Page 2 clearly recognizes the limits of laboratory testing.

Somewhere in that document is the standard sand and dust test. These tests have “evolved” over years. It is not difficult to devise a test where everything would fail. But what is the point? Creating tests that are overly severe just drives equipment weight and cost, which again, what is the point? These tests are essentially negotiated between the tester community, who want to break everything, and the material developers, who want everything to pass.

I do not doubt the test guys simply got new magazines straight out of the military inventory.

Hey where are the Stoner conspiracy theorists? They need to explain how the Army rigged these tests. Like when the Army was testing the M16 against the M14. This is another reason the Army got out of weapon design. When a contractor was competing against an inhouse Army weapon design, and doing badly, they always claimed the Army had it out for them. You see it on History Channel and repeated as Gospel. Well here, contractor designed weapons are tested against contractor designed weapons. Each contractor has equal access to Capitol Hill ($$$) to defame each other. So it is a fair fight.

 

[Greg Bell]

Well, the 416 had 7 more jams than the SCAR out of 60,000. The M4 had, ahem, SEVEN HUNDRED AND FIFTY FIVE more than the much maligned XM-8.

 

[HorseSoldier]

I think these tests put the lie to the internet wisdom regarding the XM-8. I have never EVER seen an official report listing any "melting" or jams or any other crap I have read on the net in the last 3-4 years. The XM-8 slaughtered the M4 in reliability testing. I suspect it was home cooking that kept our troops from getting the XM-8, nothing more.

I think several things happened.

First, the attempt by HK to get the XM8 was predicated on the OICW being in service so everyone not issued an OICW would have the same rifle as the KE portion of that weapon. OICW went away, or went forward into the future when it can make weight, or whatever and suddenly there's no logistical benefit to adopting the XM8 in terms of commonality.

Second, ergonomically and in terms of flexibility it's a step backward from the M4. I've not been overly impressed by the G36s I've had a chance to shoot -- nice enough, but nothing to get wowed by compared to things like an M4. I haven't shot an XM8, but my understanding is that it was not well received by the people who did trials even before the melting issue cropped up.

Third, the attempts by HK to get the contract were definitely not aimed at any kind of objective test to get the troops the best weapon out there. It was aimed at selling a bunch of G36s in space-gun shells to the Army. The attempt to adopt the G36 was sufficiently outside the bounds of usual procurement that it makes the whole M14/M16 fiasco in the 50s and 60s look like a model of program management.

Concerning the melting issue, HK did at least two revisions to the trunion design trying to solve something after the troop trials (per an HK sales rep I occasionally deal with), which strongly suggests that all did not go flawlessly and that the melting stories contain at least a kernel of truth.

 

[HorseSoldier]

I refuse to say, "I told you so."

40 years later, and the truth finally comes out.

Forty years ago you didn't know that the AR likes to be run very wet with oil or that bad mags are a bad idea in the AR and every other magazine fed weapon on the planet?

 

[chieftain]

Forty years ago you didn't know that the AR likes to be run very wet with oil or that bad mags are a bad idea in the AR and every other magazine fed weapon on the planet?

About running wet is true.

The bad magazines were one of the major issues back then too. Some things never change.

Go figure.

Fred

 

[DrewH]

SCAR-L has a standard mag well set up for STANAG/USGI 5.56mm magazines. It can use USGI magazines or anything else designed to run in an M16/M4. Since SOCOM already adopted the HK mags as the new standard issue item, there's no need for FN to seperately develop a new magazine.

A Small Arms Review article on one of the earlier versions (it was still a black rifle) of the SCAR said FN had developed a steel AR magazine for it, and had pictures of it. I have subsequently bought six FN steel AR mags that look very much like the magazine pictured. They work well, incidentally. So at least at some point FN built non USGI AR magazines. What they used in this test, who knows.

 

[Joe Demko]

As I understand the magazine issue based on a couple books and articles I read, there was originally a plan to use disposable magazines in the AR series. Single-use preloaded magazines were tried experimentally and didn't work out well. The familiar lightly constructed aluminum magazines were developed as "semi-disposable." That is to say the intention was that they'd be used a relatively few times and then discarded. Our military had no history of using disposable box magazines, so the aluminum mags were used just as box magazines had always been used. Thus, the magazine malfunctions are a result of using magazines that should have been tossed under the original parameters for their design and use. The newer magazines made by HK and others are steel and are a heavier-duty design are they not?

 

[Silvanus]

I know this says nothing about the worth of the rifle, but in a special edition of some magazine, (about contractors in Iraq), I saw one of them (who was carrying an M4 on a sling in front of his chest) posing with an XM-8...I didn't realise anybody could officially get these guns yet? Does any military or special forces use that rifle?

 

[45auto]

So, who actually makes the decision to buy whatever small arms weapon?

 

[HorseSoldier]

So, who actually makes the decision to buy whatever small arms weapon?

In theory the Army would probably administer any competition for a new service rifle (one of the other services could be put in charge of it, but with the Army being the largest end user of such it's unlikely someone else would get the nod).

The thing to keep in mind is that this test was only run to humor a Congressman, and are not part of any solicitation for a new service rifle or carbine. I suppose the issue could become enough of a political football that Congress could order the US military to open bidding for, and adopt, a new rifle, but I don't suspect that's likely unless some Democratic hopeful wants to try and make some political mileage off the issue.

 

[45auto]

The thing to keep in mind is that this test was only run to humor a Congressman, and are not part of any solicitation for a new service rifle or carbine.

I remember a very large "order" for M-4s and "stuff" was held up, around $3-4 hundred million I believe.

From the outside looking in, the M-4 did poorly...so I wonder if they will "receive" that money or whether it will be held up.

What do you or anyone think?

The H&K is a pretty "easy" changeover...yes?

 

[HorseSoldier]

The thing is, the M4 is a type-classified, standardized and all that weapon system in the US inventory. Switching to either HK design would involve putting either weapon through a bunch of testing to identify problems, correct them, etc, before deciding on a finalized form, issuing the technical data specs for it, etc. That would take time in and of itself, but politically (and logically) if we're going to buy a new rifle the whole process should be open to all the designs out there, not sole sourced to HK just because or whatever, so first there'd be the whole solicitation process, etc.

The SCAR, having already been tested and evaluated and then type-classified and all that by the folks at Crane would probably be the easier weapon to adopt in terms of the bureaucracy involved. However, I suspect that if the US Army announced it was going to buy a couple hundred thousand SCARs without an open solicitation there'd be the same sort of frothing at the mouth from firearms manufacturers as there was when HK tried to do an end run and stick up with the XM8.

 

[Don't Tread On Me]

The only thing I can see here is the design of the bolt and carrier and how they mate to the extension and with one another.


The M16 design is probably the worst ever for dust or debris. Why? Tight clearances, lots of small spaces and there are a lot of small lugs. Compare that to how the AK bolt locks into the trunion. No comparison. One has huge lugs, the other has many tiny ones. One fits relatively tight, the other has lots of play and space.


HK used a bait and switch marketing campaign. They'd claim that fouling jams the rifle. This has been proved false. Now, if going to a piston requires a different carrier, a differnet bolt and as a result a different extension - then I can see that making a difference in how well it can handle dust.


To simply say that a piston fixes everything is wrong. A piston driven AR with the same style bolt & extension as well as carrier fit is not going to be any more reliable.


We also forget that Colt and the military ALREADY tested piston'd style AR's 30-40 years ago.


For the utmost in filthy reliability, they should look into AK design concepts. Sig550 has similar carrier, bolt and lockup concept. Incorporate some of those ideas into the existing platform. I believe that's what the XCR did by using larger, but less lugs. Problem is, anything that remotely resembles the AK in design is a no-no based on the "it wasn't build here" pride/attitude factor. I guess the last time we didn't mind was in 1903.


For me, it doesn't matter. I don't live in the desert. I won't be crawling through mud or snow. My gun needs to go bang under pretty much ideal conditions. Not much can interfere with the gun during range use. Not much can mess with it in my home/safe. Even if the SHTF, there isn't anything in suburbia that I can think of that would challenge the rifle.

 

[Greg Bell]

Yeah, but the 550 recently lost to the 416 in the Norwegian military trials.

 

[longhorngunman]

If the military wanted help lower the failure rate as economically efficient as possible I'd think topping the M4 with the HK416 piston upper would be the best bet. Higher reliability and would still keep the same lower so that GI's would still be familiar and highly skilled with the weapon's controls. The price paid for the extra reliablility will be a loss of accuracy though. The AR's direct impingement "****'s where it eats" design may not appeal to the utmost reliability is everything crowd but it does make for one damn accurate semiauto rifle.
Plop a free-floated bull barrel on an AR action and you'll get a gun that can shoot with and outshoot many bolt action rifles.

 

[HorseSoldier]

Now, if going to a piston requires a different carrier, a differnet bolt and as a result a different extension - then I can see that making a difference in how well it can handle dust.

The 416's bolt and BCG are very, very similar to a standard M16/M4 bolt. Main difference is there's just a receiving surface to be tapped by the piston instead of the AR's gas key. It still has the star chamber and multi-lugged bolt, though (the G36 has a bolt design that looks a lot like an AR bolt as well, actually). The tolerances don't seem any looser on examples I've looked at and such, either, though if they are that might help explain the poor accuracy.

 

[GunTech]

If we are talking about a replacement, let's have a real competition. Let's have an open submission of designs and run them through all the tests. I don't want to have an HK end run, which is what it looks like HK has been trying to do for years.

I'd like a chance for any manufacturer, and particularly US based ones to enter into trials. We should have the M4 and the AK-74 for control rifles. Any replacement should significantly better the performance of both those weapons.

It's going to cost millions and take time before any new weapon system will be put into place. Let get the right one, and not another bandaid. Right now everyone is fixated on dust. What happens when the next conflict is back in the jungle, or in extreme cold?

We have a lot of data from the current conflict. Time to use it.

In the mean time, if we are looking at a new rifle, let's address the weaknesses of 5.56 for the kinds of Counter-insurgency operations that are likely to be the future of war.

 

[GunTech]

BTW, I've been playing with the Sig556 and I am fairly impressed. For those of you who like the AK, this will feel very familiar. The rails on the SWAT model make it comparable to rails on the latest version of the service rifle.

 

[Wes Janson]

What about KAC's SR-15? I'd really love to see how it compares with the 416, particularly in terms of long-term durability. http://www.knightarmco.com/images/sr15_1.html

While I appreciate the practical limits to a serious testing regimen, one still has to wonder how well each of those designs would perform were they to conduct the same test on weapons that had previously fired 10, 20, 30 thousand rounds downrange before being used in the test. And furthermore, how many breakage-related malfunctions were sustained by each rifle and model during the sand testing. I find it hard to believe that after 240,000 rounds downrange they didn't gain some interesting data on long-term durability in adverse environments.

Reliability isn't all that valuable if the rifle is going to fall to pieces after a few thousand rounds.

 

[George Hill]

They are not going to get any real Leap Ahead until the Army is willing to change magazines and calibers. The M-16 style magazine isn't that great anyways. HK's new magazines are help, but it's still a mag for a varmint gun cartridge.
6.5 Grendel, 6.8SPC, 25WSSM, 7MM SAUM, take your pick... until they pick a better cartridge, the gun is still nothing more than a glorified .22 mag.
Ditto the SIG 556. Great system in there... I really like it. Just wish it was in something different than .223.