Our Gemtech G5 failed at 750 rounds.

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Our Gemtech G5 failed at 750 rounds.

Post by silencertalk » Thu Jun 07, 2007 4:59 pm

We got a brand new Gemtech G5 about a week ago and decided to duplicate the test that a military group did to six of our cans.

The test was as follows:

Take an HK-416 and fire eight magazines. First mag semi auto, second mag full auto, third mag semi auto, etc -- for 8 mags. Then let it cool. In the real military test, they did not let the can completely cool. In this test, we did.

Repeat this three more times, for a total of 960 rounds. The idea is that eight magazines is a battle load, so this would simulate four firefights. It is a tough but reasonable test for a serious user. All six of our silencers survived this test.

First problem -- the G5 flash suppressor is not HK-416 compatible. We were able to get it to work with spacers (not recommended, but we checked it after a few shots and there was no bullet contact).

I videoed the entire test. I am away from home, and may not be able to post the video until next week, so I will give a report for now:

During the first eight mags, it was clear the can was not going to survive. It seemed to be puking it guts after five mags and big fireballs were coming out of it. Around this time, the mount came unscrewed on its own (not the flash suppressor, but rather the part in the middle of the can). I could call this a failure, but since we could tighten it, we decided to proceed.

We let the can air cool for about 10 minutes and then helped the can to cool completely with some water. Then started with the second 240 rounds. Then we let it cool completely again, and proceeded with the third batch of magazines. Then we let it cool completely once more, and started the final batch of mags.

Two magazines into this, I noticed the can seemed to be bulging in the middle. I shook the rifle and could see the can flopping around limp. I halted the test and noticed that the roll pin which holds the mount to the silencer main body failed, and the can unscrewed. I stopped the test six magazines early as this was a catastrophic failure and not field-repairable. This is an area that I would recommend be welded.

We let the can cool, and could hear parts shaking inside. I was surprised because Gemtech has told me that for the last few years, their silencers were welded inside. The mount halfway unscrewed on its own, and had I not noticed it, I am sure it would have blown down range.

I looked into the back cavity and I could see the baffles were not secured. We tapped the can and the baffles all fell out. As you can see from the photos, there is no evidence of any welding at all. Also the roll pin which holds the Inconel insert into the stainless blast baffle (apparently a cost-saving measure from using a real Inconel blast baffle) cracked through the side of the baffle. I also noticed that the Titanium around the flash suppressor area had fractured in several places. Again, no surprise as Ti is not a high-temp metal. See this: viewtopic.php?t=4780

The spring in the BiLock mount, by the way, has lost its strength from the heat. That makes sense, as springs are generally only good to 600 degrees, so one would expect them to fail if you put one inside the blast chamber of a silencer.
The claims of one vocal critic who has not looked closely at the G5 mount notwithstanding, the spring is not subject to the heat and flame of the entrance chamber. It is not only isolated from the entrance chamber, but our thermal measurements ahow that it remains minimally cooler than did the spring in the older M4-96D (where we had no spring failures either).

Philip H. Dater

The G5 mount never got stuck for me during this test, as has happened with the M4-96D mount.


Click for larger images.

Image
Assembly

Image
Not welded. PhD of Gemtech told me they have been welding cores for a few years but that does not appear to be accurate.

Image
Components.

Image
Stainless blast baffle with Inconel insert in center. Pinned in place.

Image
Cracks, chips, and fractures in Titanium.

Image
Cracks on back of blast baffle.

Image
Hole around roll pin has failed.
Last edited by silencertalk on Thu Jun 07, 2007 6:10 pm, edited 5 times in total.

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aarudd
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Post by aarudd » Thu Jun 07, 2007 5:08 pm

WOW, I am really glad I bought a M4-2000, no way hell would I take a G5 into battle.

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Post by silencertalk » Thu Jun 07, 2007 5:10 pm

Welding is important. We had discussed this before:
Then bigbore replied:
The welding paranoia is bullshit started by competitors to make tax stamp buying folks think Gemtech is a weaker suppressor.... I have yet to hear about any Gemtech can failing for any reason.
viewtopic.php?t=6398

This is how an AAC core looks before it is stuffed into the outer-tube:

Image
Last edited by silencertalk on Thu Jun 07, 2007 5:11 pm, edited 1 time in total.

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Post by cqbdoc10 » Thu Jun 07, 2007 5:11 pm

Its a damned conspiracy, I say!

A conspiracy!

:D
1) People often ask the U.S. what our secret defense is against terorists. We simply reply....Chuck Norris.

2) Jack Bauer does not let women on top during sex. Why? Jack Bauer never fucks up....

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Post by bmanka » Thu Jun 07, 2007 5:12 pm

What's the deal with the last baffle photo? Is that the inconel insert you were referring to?
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Post by cyclone72 » Thu Jun 07, 2007 5:19 pm

:shock: .I wonder if Gemtech will respond too this.Ill bet someone will post a mirror of this in Arfcom.Thats one sad can.

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Post by cqbdoc10 » Thu Jun 07, 2007 5:22 pm

But its a Dr. Dater can.

He is THE silencer GOD.

There must have been some tampering!

:lol:
1) People often ask the U.S. what our secret defense is against terorists. We simply reply....Chuck Norris.

2) Jack Bauer does not let women on top during sex. Why? Jack Bauer never fucks up....

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Post by Mongo » Thu Jun 07, 2007 5:24 pm

Image

This cracking has got me curious. Is the Inconel screwed into the baffle or just set in there with the roll pin to retain it?

304 Stainless and Inconel 600 (I assume that was the grade Gemtech uses) have very different expansion coefficients. Could differential expansion be part of the problem?

Wraith, MP5Eng and Matt what do you think?
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Post by silencertalk » Thu Jun 07, 2007 5:24 pm

bmanka wrote:What's the deal with the last baffle photo? Is that the inconel insert you were referring to?
Yes. Rather than use an Inconel blast baffle, they use a stainless blast baffle with a roll pin to affix an Inconel insert threaded in the center. This is an obvious point of failure.
Last edited by silencertalk on Thu Jun 07, 2007 5:26 pm, edited 1 time in total.

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Post by ArevaloSOCOM » Thu Jun 07, 2007 5:25 pm

I love that Dater told Kevin and Mike to "go ahead" in regards to making their own silencers........Talk about eating crow now......

"It hurts isn't?"

"It hurts"


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Post by gimp2x » Thu Jun 07, 2007 5:28 pm

rsilvers wrote:Welding is important. We had discussed this before:
Then bigbore replied:
The welding paranoia is bullshit started by competitors to make tax stamp buying folks think Gemtech is a weaker suppressor.... I have yet to hear about any Gemtech can failing for any reason.
viewtopic.php?t=6398

This is how an AAC core looks before it is stuffed into the outer-tube:

Image
and that is why I buy AAC, this is my new walllpaper

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Post by cyclone72 » Thu Jun 07, 2007 5:33 pm

gimp2x wrote:
rsilvers wrote:Welding is important. We had discussed this before:
Then bigbore replied:
The welding paranoia is bullshit started by competitors to make tax stamp buying folks think Gemtech is a weaker suppressor.... I have yet to hear about any Gemtech can failing for any reason.
viewtopic.php?t=6398

This is how an AAC core looks before it is stuffed into the outer-tube:

Image
and that is why I buy AAC, this is my new walllpaper
ditto,this is why I have 7 of their cans,My Vidar ,no worries but my Gemtech 5.7 can I dont know. :cry:

AAC has real sturdy cans .

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Post by 3101 » Thu Jun 07, 2007 5:39 pm

I actually participated in this tests. I shot the first 8 mags thru the can.
After the 5th mag I had lost confidence in the G5....I didn't think it would hold together at all. The "silencer function" had stopped...and the noise (no meter, just my ears) sounded like firing on any other indoor range with an unsuppressed AR. The muzzle flash had gone from somewhat noticeable to HUGE fireballs at this point, and the sound was that of an unsuppressed weapon.
I stopped holding it to my shoulder for a while and held it waist high for a while.....

After the first 8 mags I told RS I wasn't going to shoot it anymore....so we built a homemade "blast box" to contain the failure if it went catastrophic, and continued the test....and as he said, with 6 mags to go the can failed...

the jet of gas coming out the roll pin (as seen in the muzzle flash pics) totally removed or blasted away all traces of the pin.....and we called the test complete....

Oh yeah, the spring....ha.the spring in the bilock mount was toast after the test. you could actually bounce it on the gun, it had no strength left in it at all....

After the first 8 mags the finish of the can was gone as well, and it (the outer tube) had turned the color shown in the pics, almost a brown color.

I had a long chance to inspect the can before the test, it was intact and brand new, never fired. Nothing was shoved in it, no rigging anything, no excuses, no alabi.....the can just will not hold up....
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Post by tikkafan » Thu Jun 07, 2007 5:54 pm

CNC welding is an amazing thing.
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Post by kalikraven » Thu Jun 07, 2007 6:02 pm

OK I'm completely sold on AAC, except for the cheap .22 take apart can. Like the TAC-65
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Our Gemtech G5 failed at 750 rounds

Post by twodollarbill » Thu Jun 07, 2007 6:14 pm

Great Test Guys!!!!
Can't wait to see the video...........
Initially, where you not testing to see if the mount would fail??,
or did you really expect the can to go toast????
When are all others going to step up and be spanked the same way????
It is only time and money...and more money, which we
all have plenty of.....Right?

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Post by HandyMan » Thu Jun 07, 2007 6:16 pm

Wow. When I saw some pictures posted earlier of the G5 blast baffle, I thought the roll pin was a 'Dater hole'. How little I knew. They had to know that was a point of failure. The hole drilled for the rollpin is too close to the edge of the Inconel insert.

I thought the Inconel was 718, not 600? Even if it is, you can't blame the material. Blame the design. They might have been better off with a straight stainless blast baffle. The assembly is much weaker than a solid turned piece.

Is the bright ring at the junction of the main tube and the mount titanium? If so, why? The amount of titanium they used is not going to save much more than an ounce or so. Not worth it.

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Re: Our Gemtech G5 failed at 750 rounds

Post by silencertalk » Thu Jun 07, 2007 6:19 pm

twodollarbill wrote:Initially, where you not testing to see if the mount would fail??, or did you really expect the can to go toast????
I expected the can to fail because it was not welded, had Titanium in it, had three roll pins, and an internal spring. There was not a good chance it would pass the military test protocol.

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Post by cqbdoc10 » Thu Jun 07, 2007 6:27 pm

I thought that they had a user that fired over 100,000 rounds through his Gemtech.

How in the world then could this suppressor have failed after 750 rounds?

:?:

Was someone telling a tall tale?
1) People often ask the U.S. what our secret defense is against terorists. We simply reply....Chuck Norris.

2) Jack Bauer does not let women on top during sex. Why? Jack Bauer never fucks up....

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Post by 3101 » Thu Jun 07, 2007 6:29 pm

no way in hell I believe 100K rounds out of a Gemtech can.....
They sell these G5's for something like 895 bucks retail.....
Mr. Burns: This anonymous clan of slack-jawed troglodytes has cost me the election, and yet if I were to have them killed, I would be the one to go to jail. That's democracy for you.
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Post by silencertalk » Thu Jun 07, 2007 6:31 pm

cqbdoc10 wrote:I thought that they had a user that fired over 100,000 rounds through his Gemtech.

How in the world then could this suppressor have failed after 750 rounds?

:?:

Was someone telling a tall tale?
The 100,000 round quote from Gemtech is laughable. They also have ads now on the back of magazines quoting 225,000 rounds for a Raptor. I will have to call BS on both.

Image

"100,000 rounds, said my wife, Morgan Fairchild, whom I've seen nakid."

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Post by cqbdoc10 » Thu Jun 07, 2007 6:37 pm

I wonder if Gem-tech will atleast try to defend this outcome as an anomaly.
1) People often ask the U.S. what our secret defense is against terorists. We simply reply....Chuck Norris.

2) Jack Bauer does not let women on top during sex. Why? Jack Bauer never fucks up....

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Post by silencertalk » Thu Jun 07, 2007 6:40 pm

Their best defense is to say it was not designed for this kind of hard use -- however, there is no denying it is an $875 silencer and an M4-1000 is a lot more durable and lightweight and $325 less.

http://www.gem-tech.com/G5.html
If you want “high speed low drag” this is it. Every component of this suppressor
has been critically assessed, shot hard, improved upon, thought through, and tested tough to become the new standard in 5.56mm quick mounting suppressors. Lighter, stronger, quieter, more durable and maintenance-free, the G5 is made for those that demand the apex of performance.

Titanium, stainless steels, and inconel are mated throughout the G5 to ensure the right material for each task..
Let's face it -- a test can be designed to make anything fail. But this test was not designed to achieve failure -- it was designed to simulate four firefights in combat and see what products are suitable for that. It would still be fine for recreational shooters but would only make sense if it cost $150 less than an M4-1000. It would be a good value at $400.
Last edited by silencertalk on Thu Jun 07, 2007 6:45 pm, edited 3 times in total.

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Post by cqbdoc10 » Thu Jun 07, 2007 6:43 pm

Maybe "shot hard" means they had fired the test rifle in a semi-auto manner at a rate of 1 shot every 10 seconds.
1) People often ask the U.S. what our secret defense is against terorists. We simply reply....Chuck Norris.

2) Jack Bauer does not let women on top during sex. Why? Jack Bauer never fucks up....

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Post by 3101 » Thu Jun 07, 2007 7:04 pm

Let me analyze this based on what I saw today....
"high speed-low drag" = The thing rattled on the end of the mount
"critically assessed"= in what way?????
"shot hard"= BS...I call it....
"tested tough"= no way dude
"stronger more durable"= this is getting funny....you gotta be kidding
"right material for each task"= WRONG AGAIN....I don't know a damn thing about metal...but even a dimwit hillbilly like me knows you can't put roll pins in a blast chamber of a centerfire rifle can that is exposed to FA/SA fire and think it will last....
Mr. Burns: This anonymous clan of slack-jawed troglodytes has cost me the election, and yet if I were to have them killed, I would be the one to go to jail. That's democracy for you.
Smithers: You are noble and poetic in defeat, sir.

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