Dirty Rifles

[halmbarte]

Took some rifles and rock dust out to the range a couple weeks ago. We dusted a Mini-14, a AR15, Beretta ARX, FN SCAR, and a Arsenal SKR-107FR (AK47).

Things did not turn out as you might expect: http://www.youtube.com/watch?v=synlZgnTnXg

H

[VIP3R 237]

Did you retry the arsenal by chance? The scar surprises me.

[556Cliff]

Surprised to see someone actually cover some quality rifles with dirt.

I'm also a little surprised to see the SCAR and the Arsenal AK fail so early.

[halmbarte]

Did you retry the arsenal by chance? The scar surprises me.

No, that was the first run for the AK. I had assumed* that it was going to outlast all the other ones, which is why I brought the pile of AK mags.

So much for assumptions.

H

*I've shot that rifle for literally years at the local rifle match, probably has 3,000 rounds through it, and it's always been utterly reliable.

[556Cliff]

Specs on the AR? Also what brand of CLP was used on the AR?

[halmbarte]

Specs on the AR? Also what brand of CLP was used on the AR?

Franken AR with mostly BCM upper, Bushmaster stripped lower populated via CMMG except for the ALG trigger/hammer set.

Royco CLP, which was used on all the rifles except the 1st run with the Mini-14.

H

[diving dave]

Those AR's are so unreliable.....:jester:..The AK choking so early surprised me.

[Doc Safari]

Those AR's are so unreliable.....:jester:..The AK choking so early surprised me.

I can't remember if I read it somewhere, or if I talked to an armorer who came back from the sandbox, but the saying was "sand in the chamber is sand in the chamber." It doesn't matter how reliable a weapon's reputation normally might be, if there's debris in the chamber it's going to seize up.

The AK probably choked because the ejection port is an open design and the first round fed enough sand into the chamber to make it stop.

[VIP3R 237]

Very true, the Scar is the same way. If you get your rounds dirty they struggle to chamber.

[Uprange41]

I can't remember if I read it somewhere, or if I talked to an armorer who came back from the sandbox, but the saying was "sand in the chamber is sand in the chamber." It doesn't matter how reliable a weapon's reputation normally might be, if there's debris in the chamber it's going to seize up.

The AK probably choked because the ejection port is an open design and the first round fed enough sand into the chamber to make it stop.

This. Sand in the chamber is what it is. The AR had the dust cover closed, so there was likely very little actual sand in the system. Dust, sure, but sand? No. As posted on a different forum for this same video.... A cursory tap on the table would have likely changed the results for the others.

[Doc Safari]

I'm also thinking that a realistic dust and/or sand test would simulate how sand gets into a weapon during combat:

1. Soldier drops weapon into sand, ejection port down.
2. Nearby explosion or other action blows dirt and debris into ejection port.
3. Soldier "digs in" and gets dirt/sand into action


All of these things occur very fleetingly, and what gets in during a few seconds is all that gets in.

The YouTube test is really good at showing what might happen if your weapon was buried to hide it from confiscation or something, i.e., the gun is buried and then unearthed for use as action is anticipated.

I'm wondering if standing over the weapon with a sifter deliberately coating it with debris is overkill. Perhaps that's the point?

If the gun survives dirt and sand overkill, it should be good to go in a normal dirt-and-debris environment?

[556Cliff]

It has been pointed out that the SCAR is being tested with the gas adjustment selector set to the suppressed mode. Wouldn't this cause a problem?

[Uprange41]

I'm also thinking that a realistic dust and/or sand test would simulate how sand gets into a weapon during combat:

1. Soldier drops weapon into sand, ejection port down.
2. Nearby explosion or other action blows dirt and debris into ejection port.
3. Soldier "digs in" and gets dirt/sand into action


All of these things occur very fleetingly, and what gets in during a few seconds is all that gets in.

The YouTube test is really good at showing what might happen if your weapon was buried to hide it from confiscation or something, i.e., the gun is buried and then unearthed for use as action is anticipated.

I'm wondering if standing over the weapon with a sifter deliberately coating it with debris is overkill. Perhaps that's the point?

If the gun survives dirt and sand overkill, it should be good to go in a normal dirt-and-debris environment?

Pouring and all over the gun is, quite frankly, irrelevant.

If you bury the gun, you will have dirt coming in from the top, not every side as with rotating and pouring. If a blast goes off near you, but far enough that your rifle's functionality is of immediate concern, it's not going to be as concentrated as with just pouring sand. If you drop the rifle, pick it up and shake it off.

But most importantly, if your rifle does malfunction as a result of sand or dust, clear the malfunction, bang it on the ground with the action open, and then keep going.

The insistence on a perfectly infallible rifle is a goal of the inexperienced (not calling you out, Doc, just a general statement). Malfunctions are to never be assumed a moot concern. What separates a competent tactician from the rest is the ability to diagnose and clear whatever is stopping them, rather than picking whatever rifle passes this test but not another, or vice versa.

[halmbarte]

The AR had its dust cover closed for the 1st dusting, as did the AK. The dust cover was open for the 2nd and subsequent applications of dust.

Was dusting after each ten rounds overkill? Yes. From the last time I did this I knew that most rifles can go for one dusting and ten rounds. I wanted each rifle to be pushed until it failed, or two full mags were fired.

The SCAR has had the gas screw changed out so the 'suppressed' setting is enough to lock the bolt open on a empty mag, and then up two screw sizes. I keep the 'normal' setting for adverse conditions. But since I was failing rifles for failing once, it didn't seem fair to let the SCAR fail and then change the gas setting. I could have also put the ARX in adverse gas after it failed, but didn't either.

H

[Doc Safari]

The insistence on a perfectly infallible rifle is a goal of the inexperienced (not calling you out, Doc, just a general statement). Malfunctions are to never be assumed a moot concern. What separates a competent tactician from the rest is the ability to diagnose and clear whatever is stopping them, rather than picking whatever rifle passes this test but not another, or vice versa.

I don't know why you're applying that to me. I'm the one always telling my girlfriend: nothing is 100% reliable. I'm not expecting an infallible rifle, I was just critiquing how realistic the test was.

[Uprange41]

I don't know why you're applying that to me. I'm the one always telling my girlfriend: nothing is 100% reliable. I'm not expecting an infallible rifle, I was just critiquing how realistic the test was.

I said I'm not calling you out... Just was addressing a different point in the same post.


The insistence on a perfectly infallible rifle is a goal of the inexperienced (not calling you out, Doc, just a general statement). Malfunctions are to never be assumed a moot concern. What separates a competent tactician from the rest is the ability to diagnose and clear whatever is stopping them, rather than picking whatever rifle passes this test but not another, or vice versa.

Apologies if it came across that way.

[Iraqgunz]

I don't know of any time when I was overseas or elsewhere, where the weapon was that dirty.

[Iraqgunz]

People that "bury" weapons from same imaginary confiscation by the man, usually wrap them or put them in tubes.


I'm also thinking that a realistic dust and/or sand test would simulate how sand gets into a weapon during combat:

1. Soldier drops weapon into sand, ejection port down.
2. Nearby explosion or other action blows dirt and debris into ejection port.
3. Soldier "digs in" and gets dirt/sand into action


All of these things occur very fleetingly, and what gets in during a few seconds is all that gets in.

The YouTube test is really good at showing what might happen if your weapon was buried to hide it from confiscation or something, i.e., the gun is buried and then unearthed for use as action is anticipated.

I'm wondering if standing over the weapon with a sifter deliberately coating it with debris is overkill. Perhaps that's the point?

If the gun survives dirt and sand overkill, it should be good to go in a normal dirt-and-debris environment?

[diving dave]

It has been pointed out that the SCAR is being tested with the gas adjustment selector set to the suppressed mode. Wouldn't this cause a problem?

Just watched that vid again, and it would be nice to see that test run again with A) GI mags for the SCAR not aftermarket and B) gas setting set correctly .

[halmbarte]

Just watched that vid again, and it would be nice to see that test run again with A) GI mags for the SCAR not aftermarket and B) gas setting set correctly .

One of the reasons for the HK mags is that they work w/o modification in the SCAR & ARX.

The SCAR has a different gas screw fitted to allow for normal and adverse gas settings, since a suppressed setting would currently be wasted.

For what it's worth, I thought that the SCAR would beat the AR and maybe the AK. The ARX was kinda a ringer, since they are new.

H

[firefighter37]

OP, thank you for this video. I thought it was a fair test and all the controllable variables were pretty equal. I applaud your efforts.

I was surprised the AK and SCAR bowed out as fast as they did.

[farmhard]

thanks for a great video. im always impressed what a good ar15 can be subjected to and still run. in my opinion the way the ar vents is excess gas has lots to do with their reliablity in these fine dust tests.

[Leuthas]

I've seen so many of these tests over the last two decades I rarely comment.

From my observations there is one thing that remains true - no matter how consistent the 'testing,' the results are not.

[00stormbringer]

Which mm gas screw did you use for the SCAR 16? Thanks!

[halmbarte]

I took the SCAR* out today to check zero and tune the gas system.

The gas regulator was set to the suppressed setting, the rifle was clean and generously lubricated with CLP. Ammo was Danish SS109 NATO spec ammo. I started with a 1.00mm gas screw and kept increasing the size until the bolt hold open tripped and held the bolt back.

The bolt carrier came back enough to activate the BHO with the 1.35mm gas screw, and would not trip the BHO with a 3.30mm gas screw. I checked each gas screw 3 times and with 2 different mags with repeated results.

I want to have a little more then the bare minimum energy so I then went to a 1.45mm gas screw to confirm operation. The rifle functioned normally w/o any problems.

H

[azeriosu85]

Liked the "FDE" color of that ARX while dirty:p

Overall I have been more and more impressed with the ARX