CZ Bren 2 - Page 57

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CZ Bren 2 (Page 57 of 102)

morho Joined Apr 2019 Posts 20 EE 0% (0) CZE	Posted: 9/6/2020 6:36:13 AM EDT [#1] Quote History Originally Posted By Kian503: Now we know why the GIGN guy was so angry. View Quote Where can I learn more about it? Thanks!

Kian503 Joined Jul 2020 Posts 17 EE 0% (0) OR, USA	Posted: 9/6/2020 8:04:14 AM EDT [#2] Thank you Tim for all your efforts and Jason for being so kind! I would gladly send my gun into CZ so they can take a look at it but they did not get back to me when I filled out a contact us form. Should I try a different means of communication?

Kian503 Joined Jul 2020 Posts 18 EE 0% (0) OR, USA	Posted: 9/6/2020 8:06:21 AM EDT [#3] Quote History Originally Posted By morho: Where can I learn more about it? Thanks! View Quote Go to page 55 of this thread and scroll down to close to the end. You will see the picture of the Angry GIGN.

morho Joined Apr 2019 Posts 21 EE 0% (0) CZE	Posted: 9/6/2020 8:15:04 AM EDT [#4] Ah. Joke

bfoosh06

Happy to be a Member

Joined Sep 2008
Posts 11669
EE 0% (0)

NT, USA

Posted: 9/6/2020 8:19:36 AM EDT

[#5]

Quote History

Originally Posted By MilitaryArms:
Hey guys,

Yes, when Zach at CZ-USA heard of our test from my Instagram post he gave me a call which was after I had shot the test video, edited it and posted it to our Patreons. He said that CZ-USA is not being dismissive of the problem however he claimed they haven't gotten enough guns sent back to them to diagnose the problem. He did not deny a problem exists in my conversation with him. So far they've only had a handful of guns sent in (he didn't specify the number) and they need more of the problem guns to be sent in so they can figure out the issue. They don't want to send out parts on speculation, they want the guns back so they can see the problem first hand and then come up with a solution.

The good news is that CZ-USA is paying attention as they clearly were interested in the fact I was going to conduct such a test knowing it would bring considerable attention to the problem. I fully expect CZ-USA and CZUB to find a solution once they can definitively isolate the problem. CZ is quite protective of their reputation, I don't expect them to pretend there isn't a problem.

Please, if you have a gun that's malfunctioning, don't attempt to fix it yourself by putting BCM extractor springs in it or making other modifications. This will (right or wrong) void your warranty and I don't want you guys falling into that trap. If your gun is malfunctioning I would send it to CZ. If you have any issues with their customer service, please post here or contact me. I want to know because I will do all I can to keep this moving forward.

He did tell me that there are quite a few different configurations of the guns they make for the global market. A production run could have had the incorrect parts installed. For example, if you look at the 8" barrel guns, they don't have a vent hole in the front of the gas cylinder because the guns need all the gas they can get. If you look at the gun we used (11") it has a vent hole in the front which makes for a pretty large flash in daylight. However, I've seen a couple of videos showing the stovepipes occurring and to me it doesn't seem to be a gassing issue, IMHO. I believe there's something else causing the problem.

As noted above, Jason drilled his position 3 on his gas regulator to be the same port size as my 14" barreled guns position 1. We put my gas regulator from the 14" gun in his 11"er and it was perfectly gassed with the spent cases going out to the 3 o'clock position. In the video we only fired one magazine in this setting to demonstrate how it worked and how over gassed all the guns are on their factory 1 setting. We fired over 1200 rounds of lacquered Golden Tiger ammo with several mags of Federal and S&B brass rolled in all on the factory 1 position. I will get the dimensions from Chase next week after the holiday and post the data for those who are interested in drilling their position 3 for reduced gas. Drilling your position 3 for a smaller port size will void your warranty most likely, so I would make sure your gun is working before doing this mod.

Jason's gun is an early 2Ms import, one of the first batches to come into the country after the 2s non-Americanized guns came in. It very well could be the newer guns are having the issues. These have been on the market for over a year and we're just now seeing these problems. Jason has his gun registered as a SBR and is fully kitted for defensive use. It's his "go to" gun if you will and he shoots it regularly and has since getting it. He was very nervous about the testing given what we've seen so far online, so I commend him for offering up his gun to do this rather abusive test.

I completely break the gun down after the test and examine all the parts and include detailed images in the video including looking for cracks in the bolt. I've seen one poster share a picture of a bolt said to have had only 340 rounds fired before the crack appeared.

I believe there is a problem. I think it likely has to do with something related to the bolt, extractor or chamber of newer imports. I believe at least one run of guns has something out of spec because clearly not all guns suffer from the problem. However, I've been contacted by enough people to believe something is clearly amiss. It is note worthy that Hungary has adopted the Bren 2 in 7.62x39, Pakistan is considering adoption and as we all know GIGN is using them. This is what leads me to believe there is likely a manufacturing issue with a run of guns vs. the whole design being flawed.

Now that CZ has reached out to me, I will try and stay in regular communication with them about the issue and as soon as I learn something I will share it with our audience. I did see that after talking with me Zach posted to Reddit and addressed the issue publicly, so he may make public updates going forward.

Thanks for the support everyone.

View Quote

Thank you for your info.

*Hold on to your AR-15s. Their magic must be very powerful, or they wouldn’t want them.*
JAFOM.... Just another fat old man.

________________________________

TOGC,IADC

Kian503 Joined Jul 2020 Posts 19 EE 0% (0) OR, USA	Posted: 9/6/2020 10:23:49 AM EDT [#6] Quote History Originally Posted By morho: Ah. Joke View Quote Yeah just humor not a serious situation. At least I hope not. I apologize if it was disappointing.

CavScout

I Believe In Barrel Warming

Joined Feb 2001
Posts 4820
EE 100% (35)

NV, USA

Posted: 9/6/2020 10:44:21 AM EDT

[#7]

Quote History

Originally Posted By MilitaryArms:
Hey guys,

Yes, when Zach at CZ-USA heard of our test from my Instagram post he gave me a call which was after I had shot the test video, edited it and posted it to our Patreons. He said that CZ-USA is not being dismissive of the problem however he claimed they haven't gotten enough guns sent back to them to diagnose the problem. He did not deny a problem exists in my conversation with him. So far they've only had a handful of guns sent in (he didn't specify the number) and they need more of the problem guns to be sent in so they can figure out the issue. They don't want to send out parts on speculation, they want the guns back so they can see the problem first hand and then come up with a solution.

The good news is that CZ-USA is paying attention as they clearly were interested in the fact I was going to conduct such a test knowing it would bring considerable attention to the problem. I fully expect CZ-USA and CZUB to find a solution once they can definitively isolate the problem. CZ is quite protective of their reputation, I don't expect them to pretend there isn't a problem.

Please, if you have a gun that's malfunctioning, don't attempt to fix it yourself by putting BCM extractor springs in it or making other modifications. This will (right or wrong) void your warranty and I don't want you guys falling into that trap. If your gun is malfunctioning I would send it to CZ. If you have any issues with their customer service, please post here or contact me. I want to know because I will do all I can to keep this moving forward.

He did tell me that there are quite a few different configurations of the guns they make for the global market. A production run could have had the incorrect parts installed. For example, if you look at the 8" barrel guns, they don't have a vent hole in the front of the gas cylinder because the guns need all the gas they can get. If you look at the gun we used (11") it has a vent hole in the front which makes for a pretty large flash in daylight. However, I've seen a couple of videos showing the stovepipes occurring and to me it doesn't seem to be a gassing issue, IMHO. I believe there's something else causing the problem.

As noted above, Jason drilled his position 3 on his gas regulator to be the same port size as my 14" barreled guns position 1. We put my gas regulator from the 14" gun in his 11"er and it was perfectly gassed with the spent cases going out to the 3 o'clock position. In the video we only fired one magazine in this setting to demonstrate how it worked and how over gassed all the guns are on their factory 1 setting. We fired over 1200 rounds of lacquered Golden Tiger ammo with several mags of Federal and S&B brass rolled in all on the factory 1 position. I will get the dimensions from Chase next week after the holiday and post the data for those who are interested in drilling their position 3 for reduced gas. Drilling your position 3 for a smaller port size will void your warranty most likely, so I would make sure your gun is working before doing this mod.

Jason's gun is an early 2Ms import, one of the first batches to come into the country after the 2s non-Americanized guns came in. It very well could be the newer guns are having the issues. These have been on the market for over a year and we're just now seeing these problems. Jason has his gun registered as a SBR and is fully kitted for defensive use. It's his "go to" gun if you will and he shoots it regularly and has since getting it. He was very nervous about the testing given what we've seen so far online, so I commend him for offering up his gun to do this rather abusive test.

I completely break the gun down after the test and examine all the parts and include detailed images in the video including looking for cracks in the bolt. I've seen one poster share a picture of a bolt said to have had only 340 rounds fired before the crack appeared.

I believe there is a problem. I think it likely has to do with something related to the bolt, extractor or chamber of newer imports. I believe at least one run of guns has something out of spec because clearly not all guns suffer from the problem. However, I've been contacted by enough people to believe something is clearly amiss. It is note worthy that Hungary has adopted the Bren 2 in 7.62x39, Pakistan is considering adoption and as we all know GIGN is using them. This is what leads me to believe there is likely a manufacturing issue with a run of guns vs. the whole design being flawed.

Now that CZ has reached out to me, I will try and stay in regular communication with them about the issue and as soon as I learn something I will share it with our audience. I did see that after talking with me Zach posted to Reddit and addressed the issue publicly, so he may make public updates going forward.

Thanks for the support everyone.

View Quote

Awesome, thanks for everything you do MAC.

KP49

Joined Jun 2012
Posts 403
EE 100% (9)

TN, USA

Posted: 9/6/2020 1:27:16 PM EDT

[#8]

FWIW I recently acquired an early 11" 7.62x39 that has worked 100% with anything I have put thorough it. When I first bought it I used it clean out my trash 7.62x39 stash that has been building for 10 years. Everything from brass hunting ammo to spam can leftovers to 30 year old Norinco x39, about 250 rounds, and never had an issue except for a couple dead primers. It is a bit overgassed and ejection can vary but I would say 1-2 o'clock most of the time.

I fired about 300 rounds of S&B brass x39 and had no problems with that either, now that I am out of the S&B I'll be back to wolf/tula and I'm curious to see how it runs. Except for the firing pin safety and hammer face not a lot of wear anywhere.

Bolt on the pistol is marked '18, it has 14x1 LH threaded barrel and the lower doesnt have the extra little tab to stop the hammer. I assume it was one of the earlier Ms pistols having those features. Of course after reading this thread and seeing the cracked bolt and stovepipes I'm getting a little concerned and I hope its something that can easily be corrected and it isnt something that starts with higher round counts.

MilitaryArms

Sturmgewehre

Joined Jan 2001
Posts 3352
EE 100% (7)

IN, USA

Posted: 9/6/2020 3:24:22 PM EDT

[#9]

Quote History

Originally Posted By KP49:
FWIW I recently acquired an early 11" 7.62x39 that has worked 100% with anything I have put thorough it. When I first bought it I used it clean out my trash 7.62x39 stash that has been building for 10 years. Everything from brass hunting ammo to spam can leftovers to 30 year old Norinco x39, about 250 rounds, and never had an issue except for a couple dead primers. It is a bit overgassed and ejection can vary but I would say 1-2 o'clock most of the time.

I fired about 300 rounds of S&B brass x39 and had no problems with that either, now that I am out of the S&B I'll be back to wolf/tula and I'm curious to see how it runs. Except for the firing pin safety and hammer face not a lot of wear anywhere.

Bolt on the pistol is marked '18, it has 14x1 LH threaded barrel and the lower doesnt have the extra little tab to stop the hammer. I assume it was one of the earlier Ms pistols having those features. Of course after reading this thread and seeing the cracked bolt and stovepipes I'm getting a little concerned and I hope its something that can easily be corrected and it isnt something that starts with higher round counts.

View Quote

If you've fired all that without issue I suspect your pistol is fine. I've tried to find as many accounts of problems as I can and the vast majority of the problems I've found manifest themselves fairly early on. I read one account where it was claimed to have started after 2500 rounds. Jason's gun is at least to 2500 rounds and in the video I will release in a week or so will show the bolt head (lack of cracks) and close-ups of other parts.

Clearly there are good pistols and there are some problematic pistols. Again, I don't believe the design itself is flawed given military acceptance the gun in this caliber has already received. I believe there was a problem in manufacturing for a specific lot of guns. However, this is pure speculation on my part. I'm basing this on the fact the guns have been on the market for a year or so and only now are we learning of these problems.

I wish I had the money to go buy a new pistol of recent production to test. I would like to see the failures first hand and then start swapping parts with Jason's gun, that we know works, until we find the culprit.

WWW.MILITARY-ARMS.COM

JK-919 Joined Feb 2013 Posts 1041 EE 100% (3) NC, USA	Posted: 9/6/2020 5:37:04 PM EDT [#10] Has this been affecting a specific length of barrel more, or is it all 7.62 guns? I was considering a 14" gun. Also glad you're back MAC, thought you got banned from here a while ago. Welcome back, great info as always.

Kian503

Joined Jul 2020
Posts 20
EE 0% (0)

OR, USA

Posted: 9/6/2020 6:04:51 PM EDT

[Last Edit: Kian503] [#11]

Hello friends! I hope everyone is having a good Labor day weekend. Just got back from more experiments in the woods.

I started with a clean gun and 100rds of Golden Tiger. If you recall my gun has been having trouble with most of my other ammo types but had run Golden Tiger without an issue.Until today I had only ran like 60 rounds of GTs through it..

First mag first round...stovepipe.

Ran the rest of the mag. Then for the next 70 rds I got 6 failures. 3 were stove pipes style and 3 failures where the empty casing and the next round jammed up together. One time the empty casing completely 180 and the bolt jammed the rear into the star portion of the chamber. I had to use pliers to pull the steel case out other wise I would have been done.

Ejection was also inconsistent. Sometimes the empty cases would hit my left hand thumb over the bore.

Then I ran 60 rounds of brown bear subsonic with my Wolfman suppressor and standard gas setting with no issues. It even locked the bolt back on the last round. The ejection was consistent. Then I decided to run a some of the brown bear supers with the suppressor that was consistently causing stovepipes. It ran the whole mag but it was over gassed because the bolt cycling was much more violent and the empty casings were being ejected far.

Lastly, I took the suppressor off and loaded another mag of the same brown bear supers and i got a stove pipe within 5 rounds. Gave up on that ammo. Also tried WOLF lacquer coat bimetal copper jacket. Same result stove pipe within the first 5 rounds.

I definitely would like to send my gun to CZ. In the past 500 rounds or so I have had probably about 40-50 failures now. I should fill out a warranty claim correct?

KP49

Joined Jun 2012
Posts 404
EE 100% (9)

TN, USA

Posted: 9/6/2020 6:05:53 PM EDT

[#12]

Quote History

Originally Posted By MilitaryArms:
If you've fired all that without issue I suspect your pistol is fine. I've tried to find as many accounts of problems as I can and the vast majority of the problems I've found manifest themselves fairly early on. I read one account where it was claimed to have started after 2500 rounds. Jason's gun is at least to 2500 rounds and in the video I will release in a week or so will show the bolt head (lack of cracks) and close-ups of other parts.

Clearly there are good pistols and there are some problematic pistols. Again, I don't believe the design itself is flawed given military acceptance the gun in this caliber has already received. I believe there was a problem in manufacturing for a specific lot of guns. However, this is pure speculation on my part. I'm basing this on the fact the guns have been on the market for a year or so and only now are we learning of these problems.

I wish I had the money to go buy a new pistol of recent production to test. I would like to see the failures first hand and then start swapping parts with Jason's gun, that we know works, until we find the culprit.

View Quote

I'm hoping its just some isolated guns/bad parts. I havent removed the extractor to look for cracks, mine looks like the pin is peened for retention on both ends and I dont want to fix what isnt broke just yet.

I was more than happy with this until a couple days ago when I checked this thread to see if there were any new parts available and seen the extraction issues so now I'm worried lol.

Thanks for the reply.

Smurgeon

Joined Sep 2015
Posts 373
EE 100% (58)

WA, USA

Posted: 9/7/2020 2:12:10 AM EDT

[#13]

I'm not having any of the FTE problems some members are having, but the gas regulator has been broken on mine since April and CZ still doesn't have spare parts and will only fix it if I send the whole rifle in (SBR'd it, so don't want to go this route).

Who the fuck sells an entire rifle/pistol platform without any parts support? It's been on the market for 2 years now and still nothing.

MilitaryArms

Sturmgewehre

Joined Jan 2001
Posts 3353
EE 100% (7)

IN, USA

Posted: 9/7/2020 3:34:34 PM EDT

[#14]

Quote History

Originally Posted By KP49:

I'm hoping its just some isolated guns/bad parts. I havent removed the extractor to look for cracks, mine looks like the pin is peened for retention on both ends and I dont want to fix what isnt broke just yet.

I was more than happy with this until a couple days ago when I checked this thread to see if there were any new parts available and seen the extraction issues so now I'm worried lol.

Thanks for the reply.

View Quote

The extractor pins are staked in place. Why, I have no idea.

Could folks having issues post a picture of their extractor claw in good light? Here's what Jason's claw looks like:

Attached File

When compared to my like new bolt (only 200 rounds through it) the only difference I can see is that it's slightly eroded right at the sharpest edge of the claw. Below is my like new claw/bolt.

Attached File

WWW.MILITARY-ARMS.COM

Kian503 Joined Jul 2020 Posts 21 EE 0% (0) OR, USA	Posted: 9/7/2020 4:28:04 PM EDT [Last Edit: Kian503] [#15] Here are pictures of my extractor and bolt.

MilitaryArms

Sturmgewehre

Joined Jan 2001
Posts 3354
EE 100% (7)

IN, USA

Posted: 9/7/2020 6:35:52 PM EDT

[#16]

Quote History

Originally Posted By Kian503:
Here are pictures of my extractor and bolt.

View Quote

Your extractor still looks new like the one in my Bren 2s (predecessor to the Ms). Can you see the wear on Jason's extractor? Even with that minute wear his gun still runs fine. I'm curious if problem guns have more wear on them, or perhaps have a different profile. The stovepipe failures would seem to point to an extractor problem, ejector problem, or a chamber problem (or even perhaps a headspace problem).

WWW.MILITARY-ARMS.COM

Kian503

Joined Jul 2020
Posts 22
EE 0% (0)

OR, USA

Posted: 9/7/2020 7:14:26 PM EDT

[Last Edit: Kian503] [#17]

Quote History

Originally Posted By MilitaryArms:
Your extractor still looks new like the one in my Bren 2s (predecessor to the Ms). Can you see the wear on Jason's extractor? Even with that minute wear his gun still runs fine. I'm curious if problem guns have more wear on them, or perhaps have a different profile. The stovepipe failures would seem to point to an extractor problem, ejector problem, or a chamber problem (or even perhaps a headspace problem).

View Quote

Yes my gun is brand new basically (14" Bren 2MS 19 on the bolt next to serial#). It only has about 500 rounds through it with about 140 rounds of that suppressed with the standard gas setting. I bought it from Battle Hawk Armory in June. Out of the box it was fine but ever since my first range trip it has been giving me odd issues. If you scroll up just a post or two you can see my most recent range trip and one of the the failures I experienced (finally figured out how to add photos).

I honestly do not have a clue what is wrong. From my impressions its seems like its behaving like its under gassed with commercial ammo on the standard gas setting. This could be due to the many issues you pointed out.

I started my account here so I could get some help with my gun as I really enjoy it just not all the failures.

Thank you again Tim and for being so kind to help us out with this issue and please thank Jason for being so brave to let you try to break his gun for our benefit!!

Sweet5ltr

Joined Feb 2014
Posts 98
EE 100% (8)

FL, USA

Posted: 9/7/2020 8:21:59 PM EDT

[Last Edit: Sweet5ltr] [#18]

Failed To Load Title

https://www.youtube.com/watch?v=ePkTO2SP39c

Okay, I'll say that this was a major fail today for the CZ. Firearm is absolutely not reliable, I was prepared and already placed the charging handle on the right and lubed the bolt to mitigate potential failures. I expected to run it hard today and go through 900 rounds of Golden Tiger, but I couldn't get through a single magazine without an FTE and stopped at 120 rounds.

Ran it on adverse those last few rounds, ejection is all over the place, two rounds to the 2'o'clock and one to the 5'o'clock behind me.

MilitaryArms

Sturmgewehre

Joined Jan 2001
Posts 3355
EE 100% (7)

IN, USA

Posted: 9/7/2020 8:25:04 PM EDT

[#19]

Quote History

Originally Posted By Kian503:

Yes my gun is brand new basically (14" Bren 2MS 19 on the bolt next to serial#). It only has about 500 rounds through it with about 140 rounds of that suppressed with the standard gas setting. I bought it from Battle Hawk Armory in June. Out of the box it was fine but ever since my first range trip it has been giving me odd issues. If you scroll up just a post or two you can see my most recent range trip and one of the the failures I experienced (finally figured out how to add photos).

I honestly do not have a clue what is wrong. From my impressions its seems like its behaving like its under gassed with commercial ammo on the standard gas setting. This could be due to the many issues you pointed out.

I started my account here so I could get some help with my gun as I really enjoy it just not all the failures.

Thank you again Tim and for being so kind to help us out with this issue and please thank Jason for being so brave to let you try to break his gun for our benefit!!

View Quote

I went back up and looked at your post and the images.

It doesn't seem as though there are any visible differences, at least not that I can see, in your bold vs. Jason's or even mine.

It's noteworthy that you said the gun flings the brass forward to the 1 or 2 o'clock position when it's working normally. However you see erratic ejection which could be a number of things causing it. Let's assume the extractor is functioning fine because it seems to look fine. The next culprit may be the ejector. Can you test the tension on the ejector? I would field strip the gun and then take a case, hook the rim under the extractor claw and compress the ejector. Pull your finger back as to further compress the ejector spring and let it slip thus allowing the ejector to fling the case. Do it several times and see if you notice a variation in the ejector tension. It could be that it's binding up. If the ejector tension seems good then that's one more thing checked off the list of possibilities, at least for now.

If the gun throws the empties forward that means it's gassed (over gassed) properly, even if it's only in between failures. I doubt the gas port size is wrong. However, do the separate components of the gas system move freely? When you take the gas plug, piston, rod and spring out, do they all come apart easily and do they go in and out of the gun smoothly? When you are shooting, do the failures seem to increase as the gun warms up, or do they happen without any particular preconditions?

If you have a newer cell phone like an iPhone 11 that has slow motion, set it to 240fps and see if you can film the gun failing. If you have simple editing software you can slow this down even more. This will tell us if the spent case is being thrown back into the action, or if it's not making it out at all during the failure. Slow motion can tell us quite a bit. If you don't have editing software, I can PM you my email and we can setup a dropbox to get me the video file and I'll do the editing to see if we can see what's going on.

There's no need to thank me, brother. We're all in this together trying to help each other out. The only thing different about me is that I can help bring awareness to issues and apply pressure to manufacturers if needed.

WWW.MILITARY-ARMS.COM

MilitaryArms

Sturmgewehre

Joined Jan 2001
Posts 3356
EE 100% (7)

IN, USA

Posted: 9/7/2020 8:41:35 PM EDT

[#20]

Quote History

Originally Posted By Sweet5ltr:

https://www.youtube.com/watch?v=ePkTO2SP39c

Okay, I'll say that this was a major failure today. Firearm is absolutely not reliable, I was prepared and already placed the charging handle on the right and lubed the bolt. I expected to run it hard today and go through 900 - rounds, but I couldn't get through a single magazine without an FTE and stopped at 120 rounds.

Ran it on adverse those last few rounds, ejection is all over the place, two rounds to the 2'o'clock and one to the 5'o'clock behind me.

View Quote

Thank you for posting the video. The next time you're at the range can you film at higher quality (at least 1080 if not 4k) and with better lighting? I would try to lean forward out from the shade of the overhang. When you were further forward in the frame the lighting seemed better. Also, try to have someone film for you. If you have sky behind you it will make you and the gun look dark (it's called being backlit). With the camera on the table looking up, you have a lot of sky and back lighting.

I took the video and grabbed the two segments I could best use and slowed them down. I brightened it up as much as I could but still we can't see exactly what's going on in the ejection port. However, what it looks like I'm seeing is that the bolt is losing control of the spent case and is not traveling rearward with the bolt and carrier. It even looks like the gun short strokes, but that could be an optical illusion based on the poor lighting and how dark the area is around the ejection port.

Clearly the gun flings some cases forward as it should but then when it stovepipes it seems as though one of two things are happening but I can't tell for sure: 1) extractor doesn't hold on to the case long enough for it to be properly ejected or 2) the bolt/carrier is short stroking.

When it fails can you feel a reduced recoil impulse like it's short stroking?

Bren 2 slow test

https://www.youtube.com/watch?v=rlp_tJ6k1jQ

WWW.MILITARY-ARMS.COM

Sweet5ltr Joined Feb 2014 Posts 99 EE 100% (8) FL, USA	Posted: 9/7/2020 8:50:30 PM EDT [Last Edit: Sweet5ltr] [#21] Sorry Tim, drove from Orlando, back to Jacksonville, then back to the range this afternoon which is another hour away to get this quick video. We need Jason or a professional camera crew with us for sure! I uploaded the complete video in 720P, I'll crop the FTE and upload in 1080P.

MilitaryArms

Sturmgewehre

Joined Jan 2001
Posts 3357
EE 100% (7)

IN, USA

Posted: 9/7/2020 8:52:34 PM EDT

[#22]

Quote History

Originally Posted By Sweet5ltr:
Sorry Tim, drove from Orlando, back to Jacksonville, then back to the range this afternoon which is another hour away to get this quick video. We need Jason or a professional camera crew with us for sure!

I uploaded the complete video in 720P, I'll crop the FTE and upload in 1080P.

View Quote

I wish you were closer, I would meet you at the range.

If anyone is having the issue and lives near NW Indiana, please let me know. I would be glad to meet with you and use our camera gear to get some slow motion video that would likely give us a very good idea of what's going on.

WWW.MILITARY-ARMS.COM

Wespe Member Joined Mar 2002 Posts 5503 EE 100% (222) WA, USA	Posted: 9/7/2020 9:03:16 PM EDT [#23] Off topic of the 7.62 issues, but I saw Preston Precision has rails available for the MS models now. Available as a set of 3, or just a bottom rail if so desired. Look pretty sweet and should help to put something on the bottom with the weird spacing of the Mlok slots. https://www.prestonprecision.net/productscz/cz-bren-2ms-picatinny-rails

MagnusActual <<®>> Joined Oct 2007 Posts 1280 EE 100% (552) USA	Posted: 9/7/2020 9:07:54 PM EDT [Last Edit: MagnusActual] [#24] https://www.ar15.com/forums/Armory/CZ-Bren-2ms-picatinny-rail-set-from-Preston-Precision/2-515602/
	Have Gun, Will Travel

Sweet5ltr Joined Feb 2014 Posts 100 EE 100% (8) FL, USA	Posted: 9/7/2020 9:11:18 PM EDT [Last Edit: Sweet5ltr] [#25] Just wanted to get something on film, after your 1,200 round test - I'm sure you felt a bit skeptical of all the reports coming in. I'm going to tear it down in a few minutes, I'll let you know if I see anything abnormal and take a few photos. I also took pictures before I left of the extractor, I'll post those along with them.

MilitaryArms

Sturmgewehre

Joined Jan 2001
Posts 3358
EE 100% (7)

IN, USA

Posted: 9/7/2020 9:13:15 PM EDT

[Last Edit: MilitaryArms] [#26]

Quote History

Originally Posted By Wespe:
Off topic of the 7.62 issues, but I saw Preston Precision has rails available for the MS models now. Available as a set of 3, or just a bottom rail if so desired. Look pretty sweet and should help to put something on the bottom with the weird spacing of the Mlok slots.

https://www.prestonprecision.net/productscz/cz-bren-2ms-picatinny-rails

View Quote

I ordered a set of two bottom rails as I had real CZ side rails and the holes were slightly off so I couldn't get the rail to mount. I emailed them but never got resolution. I finally found a single real CZ lower.

Attached File

WWW.MILITARY-ARMS.COM

MagnusActual

<<®>>

Joined Oct 2007
Posts 1281
EE 100% (552)

USA

Posted: 9/7/2020 9:17:13 PM EDT

[#27]

Quote History

Originally Posted By MilitaryArms:
I ordered a set of two bottom rails as I had real CZ side rails and the holes were slightly off so I couldn't get the rail to mount. I emailed them but never got resolution. I finally found real a single real CZ lower.

https://www.AR15.Com/media/mediaFiles/684/IMG_8029_jpeg-1582126.JPG

View Quote View All Quotes

View All Quotes

Quote History

Originally Posted By MilitaryArms:

Originally Posted By Wespe:
Off topic of the 7.62 issues, but I saw Preston Precision has rails available for the MS models now. Available as a set of 3, or just a bottom rail if so desired. Look pretty sweet and should help to put something on the bottom with the weird spacing of the Mlok slots.

https://www.prestonprecision.net/productscz/cz-bren-2ms-picatinny-rails

I ordered a set of two bottom rails as I had real CZ side rails and the holes were slightly off so I couldn't get the rail to mount. I emailed them but never got resolution. I finally found real a single real CZ lower.

https://www.AR15.Com/media/mediaFiles/684/IMG_8029_jpeg-1582126.JPG

I ordered a set for the MS... Hopefully there's no issues like yours...

Have Gun, Will Travel

MilitaryArms Sturmgewehre Joined Jan 2001 Posts 3359 EE 100% (7) IN, USA	Posted: 9/7/2020 9:19:01 PM EDT [#28] Quote History Originally Posted By Johnny_Longslide: I ordered a set for the MS... Hopefully there's no issues like yours... View Quote Mine is the Bren 2s so perhaps that's the reason why...
	WWW.MILITARY-ARMS.COM

Tfdarchos

Joined Feb 2013
Posts 77
EE 100% (6)

WI, USA

Posted: 9/7/2020 9:40:40 PM EDT

[#29]

I'm uploading the album of my August 21st range trip where I experienced 9 malfunctions within 380rnds. All rounds shot were poly coated wolf fmj and hp. I purposely used poly coated as Mike from CZ told me that my chamber was coated in lacquer previously and that was the cause of my malfunctions. Granted I had only shot 60rnds total of lacquer coated ammo and the malfunctions happened before I had shot the golden tiger.

This range trip is just after receiving my pistol back from CZ for a second time, total time spent at their facility was 7 weeks between the two trips.

One thing I had remembered this trip is that the cases had a streak of carbon down one side.

https://photos.app.goo.gl/ibQNMMTXUk7A7UKy9

This range trip I had also swapped back to my stock handguard most of the way through the session, however I still had malfunctions.

I'm sure you have all seen it before, but this is the original video of my pistol malfunctioning.

https://youtu.be/L-cUi9Aw11g

I am hoping tomorrow that I hear more info from CZ and can get this cleared up. This pistol was meant to be a possible defensive firearm for my household, but there is no way I could ever trust it after what I have seen it do.

Magsz18

Joined Mar 2005
Posts 1763
EE 100% (90)

FL, USA

Posted: 9/7/2020 9:49:56 PM EDT

[#30]

Tim,

Thanks for keeping an eye on this and pushing the issue.

At this juncture, i'm really glad we aren't pushing the narrative that this is ammo related. While ammo is a part of the equation, there is way more going on here and CZ acknowledging that the gun SHOULD run with surplus steel cased ammo is a move in the right direction.

I have a few videos on Youtube where people are continuing to push the narrative that the ammo is what is causing the issue.

Either i'm spoiled by my collection of AR15's or I...dunno. This rifle should be able to run everything thrown at it. Some ammo types better than others (accuracy wise) like most other modern rifles.

JuanCarlos

Joined Sep 2019
Posts 32
EE 100% (2)

NC, USA

Posted: 9/7/2020 9:59:34 PM EDT

[#31]

I have the Cz Bren 2 S in 5.56 and its a great gun but I have my KAC SR-15's in 14.5" and 11.5" for my go to guns and for 762 x39 a KS47 for deer hunting/truck gun. For the money cant be beat. I would never trust my life on the x39 Bren 2 and the 5.56 Bren 2 isnt as good as a top end Ar15 in my opinion. I will be keeping my Bren 2 S as a collectors item. Tim would you agree with my comments?

MilitaryArms

Sturmgewehre

Joined Jan 2001
Posts 3360
EE 100% (7)

IN, USA

Posted: 9/7/2020 10:07:18 PM EDT

[#32]

Quote History

Originally Posted By JuanCarlos:
I have the Cz Bren 2 S in 5.56 and its a great gun but I have my KAC SR-15's in 14.5" and 11.5" for my go to guns and for 762 x39 a KS47 for deer hunting/truck gun. For the money cant be beat. I would never trust my life on the x39 Bren 2 and the 5.56 Bren 2 isnt as good as a top end Ar15 in my opinion. I will be keeping my Bren 2 S as a collectors item. Tim would you agree with my comments?

View Quote

I agree that the Bren 2s should be a valuable collectors items down the road.

As to the AR being significantly superior to the Bren 2 in 5.56, I can't really say if that's true or not. At this point the guns are brand new to the market. The AR15 is a well proven design and if you have one made by a quality manufacturer, I believe it's probably the best modern fighting rifle available. I have 30+ years experience with AR's and I trust them.

Maybe in a few years the Bren 2 will rise to the same standard. We can only speculate. If all I had were a Bren 2s in 5.56 I wouldn't feel poorly armed though. But given the choice, I would choose my AR over a Bren 2s.

WWW.MILITARY-ARMS.COM

Sweet5ltr Joined Feb 2014 Posts 101 EE 100% (8) FL, USA	Posted: 9/7/2020 10:10:11 PM EDT [#33] No reason to even post pictures of my bolt, it looks like new, no deformation on the extractor. Everything I can see here, after wiping the BCG looks perfectly fine. Very little to no build up on the gas system.

Kian503

Joined Jul 2020
Posts 23
EE 0% (0)

OR, USA

Posted: 9/7/2020 10:19:34 PM EDT

[Last Edit: Kian503] [#34]

I tested the tension on the ejector like you asked and it seems consistent. No odd variation or anything noticeable to me.

I have taken the gas system apart and cleaned it 2 times and all 3 parts do come apart easily. I can not notice anything odd about the components.

The failures have happened when the gun was warm and when the gun was totally cold. Last trip out I got a stove pipe on the very first round of the first mag on a clean lubed gun. No preconditions. The failures seem happen randomly. With specific ammo types they happen more often. No hiccups with subsonic bear running suppressed.

I have a samsung phone but i do believe it has slow motion. I can try to film it next weekend possibly with my buddies help. I am trying to contact CZ to return the weapon to them. I wish I lived around you I would totally let you take a look at it in person.

gonnasellstuff

Joined Jun 2014
Posts 346
EE 100% (65)

USA

Posted: 9/7/2020 10:25:33 PM EDT

[Last Edit: gonnasellstuff] [#35]

Quote History

Originally Posted By MilitaryArms:
I agree that the Bren 2s should be a valuable collectors items down the road.

As to the AR being significantly superior to the Bren 2 in 5.56, I can't really say if that's true or not. At this point the guns are brand new to the market. The AR15 is a well proven design and if you have one made by a quality manufacturer, I believe it's probably the best modern fighting rifle available. I have 30+ years experience with AR's and I trust them.

Maybe in a few years the Bren 2 will rise to the same standard. We can only speculate. If all I had were a Bren 2s in 5.56 I wouldn't feel poorly armed though. But given the choice, I would choose my AR over a Bren 2s.

View Quote

I sold all my Scar 16s after getting my Bren 2 S models because i believe they are superior to the scar 16. Having said that my ar15 would be grabbed first over my Bren 2. Hard to argue with over 6000 rounds with no cleaning or lube without a malfunction. I really love your viideos. Youre the Best in the business!

Kian503

Joined Jul 2020
Posts 24
EE 0% (0)

OR, USA

Posted: 9/7/2020 10:25:58 PM EDT

[#36]

Quote History

Originally Posted By Sweet5ltr:

https://www.youtube.com/watch?v=ePkTO2SP39c

Okay, I'll say that this was a major fail today for the CZ. Firearm is absolutely not reliable, I was prepared and already placed the charging handle on the right and lubed the bolt to mitigate potential failures. I expected to run it hard today and go through 900 rounds of Golden Tiger, but I couldn't get through a single magazine without an FTE and stopped at 120 rounds.

Ran it on adverse those last few rounds, ejection is all over the place, two rounds to the 2'o'clock and one to the 5'o'clock behind me.

View Quote

This is pretty much how my range experience is. Minus the multiple mags. I only have 2.

Kian503

Joined Jul 2020
Posts 25
EE 0% (0)

OR, USA

Posted: 9/7/2020 10:32:30 PM EDT

[#37]

Quote History

Originally Posted By Tfdarchos:
I'm uploading the album of my August 21st range trip where I experienced 9 malfunctions within 380rnds. All rounds shot were poly coated wolf fmj and hp. I purposely used poly coated as Mike from CZ told me that my chamber was coated in lacquer previously and that was the cause of my malfunctions. Granted I had only shot 60rnds total of lacquer coated ammo and the malfunctions happened before I had shot the golden tiger.

This range trip is just after receiving my pistol back from CZ for a second time, total time spent at their facility was 7 weeks between the two trips.

One thing I had remembered this trip is that the cases had a streak of carbon down one side.

https://photos.app.goo.gl/ibQNMMTXUk7A7UKy9

This range trip I had also swapped back to my stock handguard most of the way through the session, however I still had malfunctions.

I'm sure you have all seen it before, but this is the original video of my pistol malfunctioning.

https://youtu.be/L-cUi9Aw11g

I am hoping tomorrow that I hear more info from CZ and can get this cleared up. This pistol was meant to be a possible defensive firearm for my household, but there is no way I could ever trust it after what I have seen it do.

View Quote

Yours is also a 19 on the bolt which I think is year it was manufactured. Mine is also 19.

Sweet5ltr Joined Feb 2014 Posts 102 EE 100% (8) FL, USA	Posted: 9/7/2020 10:36:09 PM EDT [#38] Do we have a good email for someone @ CZ-USA to process the return?

MeatAxe556

Joined Apr 2011
Posts 514
EE 0% (0)

USA

Posted: 9/8/2020 12:08:00 AM EDT

[Last Edit: MeatAxe556] [#39]

Quote History

Originally Posted By MilitaryArms:
Thank you for posting the video. The next time you're at the range can you film at higher quality (at least 1080 if not 4k) and with better lighting? I would try to lean forward out from the shade of the overhang. When you were further forward in the frame the lighting seemed better. Also, try to have someone film for you. If you have sky behind you it will make you and the gun look dark (it's called being backlit). With the camera on the table looking up, you have a lot of sky and back lighting.

I took the video and grabbed the two segments I could best use and slowed them down. I brightened it up as much as I could but still we can't see exactly what's going on in the ejection port. However, what it looks like I'm seeing is that the bolt is losing control of the spent case and is not traveling rearward with the bolt and carrier. It even looks like the gun short strokes, but that could be an optical illusion based on the poor lighting and how dark the area is around the ejection port.

Clearly the gun flings some cases forward as it should but then when it stovepipes it seems as though one of two things are happening but I can't tell for sure: 1) extractor doesn't hold on to the case long enough for it to be properly ejected or 2) the bolt/carrier is short stroking.

When it fails can you feel a reduced recoil impulse like it's short stroking?

https://www.youtube.com/watch?v=rlp_tJ6k1jQ

View Quote

Would like to see some more slo mo (and even slower slow motion, if possible) of these guns when they malfunction. Especially in the second shot above, you can see a dramatic flash coming, not out of the muzzle, but out of the relief port in front of the gas plug. I'm not sure how many frames per second this video is being shot at, but it looks like the carrier is moving pretty fast and hard. The cartridge jams within a frame or so of the carrier moving back. It doesn't appear that the cartridge rim is being grasped properly out of the chamber and doesn't even get to the ejection stage.

It's hard to move the video frame by frame, but here is the rough sequence of events:

1. Frame one: trigger is pulled and recoil / muzzle flip begins and continues for another frame.

2. Next frame: Massive flash is seen coming from the relief port of the gas plug, lasts another frame or two.

3. Next frame: Carrier moves backwards and is fully extended back within one frame and stays back another frame.

4. Next frame: Spent cartridge is seen stove piped - you don't see the shell being extracted by the bolt, or (attempted) ejection.

It looks to me like the carrier / bolt is moving back so fast that that the extractor is ripped off the case rim (probably the case is still stuck in the chamber at that point, and had enough residual oomph or blowback to push itself out of the chamber, but not enough to be properly ejected).

So, I'm going to say this gun is way overgassed, probably because the gas port, either in the barrel or on the gas plug was drilled too big. That's my diagnosis...FWIW

bigjeep127

Joined Sep 2020
Posts 1
EE 0% (0)

GA, USA

Posted: 9/8/2020 1:49:20 AM EDT

[#40]

Hey folks, I'm a recent 14" 5.56 owner and am also having stovepipes, so I created an account to jump in here. I'm hopeful to see my 7.62 brothers and sisters get these problems solved because it sure sounds frustrating. Hope I don't derail the thread with my question, but I can't seem to find any 5.56 owners with my same issue...

I had shot about 500 rounds of federal 5.56 and pmc bronze .223 without a single hiccup/malfunction until I got my tax stamp and installed the Dan Haga ACR adapter and ACR stock. With the ACR adapter, I get erratic ejections and stovepipes (at about a 10-15% rate), just like the 7.62 folks are having.

Have any 5.56 owners had this problem with the ACR adapter?

I've switched between the ACR and the CZ buffer tube adapter and with the CZ adapter, I still get zero malfunctions luckily. The ejections are fairly consistent with the CZ adapter at about 1-2 o'clock. They are a bit weak, with the brass only landing maybe 3-4 feet away, but no stovepipes luckily.

I’m character restricted, continued in next post…

bigjeep127

Joined Sep 2020
Posts 2
EE 0% (0)

GA, USA

Posted: 9/8/2020 1:49:50 AM EDT

[#41]

...continued

I contacted Dan Haga and he said no one else has told him of this issue, so I'm perplexed. He was kind and offered me a refund. I should also note that the adapter did not fit at first. There was an inner radius in the slot that was interfering, I had to dremel it down to get the adapter to line up with the sling bracket screw. Dan Haga said this was a bad batch and the radius was cut too large. I don't see why this would cause stovepipe issues after I got it to fit.

I went ahead and ordered an overpriced CZ 922r kit from gunbroker, so hopefully, I don't have issues with it.

Any theories as to why the adapter would cause issues? I checked the fit and the recoil spring seems to allow for the same amount of travel of the bolt carrier with both adapters. The only difference is that the Dan Haga is much stiffer/tighter fitting. I'm thinking the bolt carrier is coming back too fast with the stiffer adapter. I find it hard to believe this would make such a big difference, but I'm not an expert. I checked the ejector spring and it seems to fling shells pretty consistently, the extractor is nice and sharp. I keep the gun very clean and well lubed between range days. I have noticed a lot of brass shavings though, wondering if the barrel lugs (is that what they're called?) are catching the brass some? The lugs have some surprisingly sharp edges from the factory, with a few small deformations. I noticed this before shooting it for the first time.

Anyways, if you read all of this I appreciate it. I'm pretty bummed to have gone through the SBR paperwork and not be able to use the ACR stock. I would've bought the CZ stock from the beginning if CZ-USA would make more than 6 of them for the whole country. Really crossing my fingers I don't have issues with the CZ 922r stock that I overpaid for. Will report back if anyone is interested.

Kian503

Joined Jul 2020
Posts 26
EE 0% (0)

OR, USA

Posted: 9/8/2020 9:45:20 AM EDT

[#42]

Quote History

So, I'm going to say this gun is way overgassed, probably because the gas port, either in the barrel or on the gas plug was drilled too big. That's my diagnosis...FWIW

View Quote

I do not think its overgassed. In my humble opinion its "behaving" as if its undergassed. I say this because with the standard gas setting and no suppressor I was getting the stove pipe failures with Brown bear supersonic. However, the same ammo with a suppressor would run with no failures (but the bolt cycling was uncomfortably violent). I assume the adverse setting feels like this.

When the stovepipes happen you can feel it. It as if the gun is short stroking like Tim mentioned.

Originally I thought maybe it was headspacing. If that is true it should happen with any ammo load correct? But it does not happen when I run it suppressed with brown bear subsonics. The gun has ran about 120 round of brown bear subsonic without an issue. The recoil impulse actually feels healthier than with standard ammo and no suppressor.

I have some spent cases I can post if anyone wants to see pics. Should I take pics of the gas system maybe someone can spot something off?

armoredman

Member

Joined Jul 2013
Posts 5089
EE 0% (0)

AZ, USA

Posted: 9/8/2020 10:29:22 AM EDT

[Last Edit: armoredman] [#43]

I finally had issues with my BREN 2 MS 11 inch 7.62x39mm...bt it was practically self induced. SOMEHOW a 5.56mm round got loaded in the mag and went WHOOSH...Pistol and I were unharmed, pride shattered - don't load magazines and talk to two different people at the same time, and keep ammo separated.
Now, past that, after a complete cleaning and inspection, I the firearm back out to the range the next day. Using the same magazine, (clear plastic original from 2018), I had two wild malfunctions, one stove pipe while one halfway in the chamber and the bolt trying to strip a third off the mag. Never saw that before. One more classic stovepipe and that mag went in the bag. I had a brand new black windowed mag loaded with 30 Tula steel, and I rattled those off with no issues whatsoever. Another 40 rounds of other various loads also went downrange with no hitch at all. I am no gunsmith, but it appeared to me that getting rid of the old clear mag helped as it was possibly damaged in the massive incident of stupid. I am not sure but I think I have about 2000 rounds through this one so far, 2018 BREN 2 MS, and only my idiocy caused issues. When I get a chance I'll see if I can post bolt face photos.

Attached File

Edit to add - the ONLY changes to this firearm is the Shockwave brace kit and the Picatinny rail adapter on the left side that I still don't have a flashlight mount for. Absolutely nothing else has been changed from the factory stock condition in which it was sent to me.

Sweet5ltr Joined Feb 2014 Posts 103 EE 100% (8) FL, USA	Posted: 9/8/2020 11:45:37 AM EDT [Last Edit: Sweet5ltr] [#44] Kian, I'm going to send my spent cases that I pulled from the stove pipes to CZ-USA as well. Do you have any pictures of your cases?

Sweet5ltr

Joined Feb 2014
Posts 104
EE 100% (8)

FL, USA

Posted: 9/8/2020 12:22:22 PM EDT

[#45]

Quote History

Originally Posted By armoredman:
I finally had issues with my BREN 2 MS 11 inch 7.62x39mm...bt it was practically self induced. SOMEHOW a 5.56mm round got loaded in the mag and went WHOOSH...Pistol and I were unharmed, pride shattered - don't load magazines and talk to two different people at the same time, and keep ammo separated.
Now, past that, after a complete cleaning and inspection, I the firearm back out to the range the next day. Using the same magazine, (clear plastic original from 2018), I had two wild malfunctions, one stove pipe while one halfway in the chamber and the bolt trying to strip a third off the mag. Never saw that before. One more classic stovepipe and that mag went in the bag. I had a brand new black windowed mag loaded with 30 Tula steel, and I rattled those off with no issues whatsoever. Another 40 rounds of other various loads also went downrange with no hitch at all. I am no gunsmith, but it appeared to me that getting rid of the old clear mag helped as it was possibly damaged in the massive incident of stupid. I am not sure but I think I have about 2000 rounds through this one so far, 2018 BREN 2 MS, and only my idiocy caused issues. When I get a chance I'll see if I can post bolt face photos.

https://www.AR15.Com/media/mediaFiles/360589/Goblin_on_line_8_19_2020_jpg-1582718.JPG

Edit to add - the ONLY changes to this firearm is the Shockwave brace kit and the Picatinny rail adapter on the left side that I still don't have a flashlight mount for. Absolutely nothing else has been changed from the factory stock condition in which it was sent to me.

View Quote

To make it look worse, my last range trip I had (5) FTE's and then fired 120-rounds without a malfunction.

This range trip, I couldn't get through a single magazine, only loaded to 20-rounds without a malfunction. Make sure you run it again soon, just to be completely sure there isn't an issue.

KP49

Joined Jun 2012
Posts 406
EE 100% (9)

TN, USA

Posted: 9/8/2020 1:02:43 PM EDT

[#46]

11" 7.62 Ms here with the tailhook mod 2 and a shimmed adapter, everything else stock. I hit the range this morning with 80 rounds of Tula 122gr fmj 'range friendly' steel cased ammo, looks poly coated. 40 rounds of 122gr fmj bi-metal Tula, and 20 rounds of 196gr brown bear lacquered subsonic.

Only had one FTE with the subsonic in the normal gas position, but those would not even cycle the action to pick up the next round or lock the bolt back on either the normal or adverse gas settings. I switched between the normal and adverse a few times and didnt really notice much difference but never once did it strip the next round from the mag.

No issues at all with the other ammo, ejection was from 1-3 o'clock now that I am paying attention. I'm at about 800 rounds now with no failures except todays's subsonic not ejecting 1 out of 20.

Stovepipes could be a combo of overgassed plus a tighter/rougher chamber that makes it even worse. I have a 14x1 LH threaded barrel, maybe its a mil contract with a little looser chamber, who knows. With so many different barrels and gas system parts you may never be able to narrow down exactly what the problem is until you start swapping parts around.

Could be certain kinds of ammo as well, I shot a lot of S&B brass cased ammo and the ejection was way more consistent, after 100 rounds there was pretty much one neat pile of brass, the tula is all over the place. I picked up some wolf military classic and poly fmj and I'll try that next time out. I with I could find more of the pre-covid S&B brass @ 32cpr, that stuff shot well and was pretty clean.

Kian503

Joined Jul 2020
Posts 27
EE 0% (0)

OR, USA

Posted: 9/8/2020 2:08:25 PM EDT

[Last Edit: Kian503] [#47]

Behold! Here some spent casings friends. Silver steel is Brown Bear 123 gr that was causing the most FTE. The set with only 7 casings is 196 Brown Bear subsonic. Lastly I have pictured 124 gr Golden Tiger that caused the 180 degree failure I pictured above. I think that is the mangled casing you are seeing in the pic on the far left. Hope this helps. Also just a note not ALL the casings look like this. These are just the worst ones I could find after looking through about 300 rounds of empty. Also I tried to orient them in the pic so they are all facing the same way in my crazy mind.

MeatAxe556

Joined Apr 2011
Posts 515
EE 0% (0)

USA

Posted: 9/8/2020 4:44:43 PM EDT

[Last Edit: MeatAxe556] [#48]

Quote History

Originally Posted By Kian503:
Behold! Here some spent casings friends. Silver steel is Brown Bear 123 gr that was causing the most FTE. The set with only 7 casings is 196 Brown Bear subsonic. Lastly I have pictured 124 gr Golden Tiger that caused the 180 degree failure I pictured above. I think that is the mangled casing you are seeing in the pic on the far left. Hope this helps. Also just a note not ALL the casings look like this. These are just the worst ones I could find after looking through about 300 rounds of empty. Also I tried to orient them in the pic so they are all facing the same way in my crazy mind.
https://i.imgur.com/jfuUxgv.jpg
https://i.imgur.com/7fdFOKK.jpg
https://i.imgur.com/lJiYMpb.jpg
https://i.imgur.com/wpAfuiZ.jpg
https://i.imgur.com/yro3qZq.jpg
https://i.imgur.com/IlS2XF1.jpg

View Quote

OK, so weren't you saying that the Brown Bear 196 gr. subsonic load is the only round cycling reliably through your gun? The spent shells look fine.

https://www.k-var.com/ammo-brown-bear-762x39-196gr-fmj-500-rounds

Regular Brown Bear and GT 123 gr. have FTE issues and the shells come out mangled. Those two rounds have more than twice as much muzzle velocity and 3 times the muzzle energy as the Brown Bear subsonic round.

So what does that tell you? Is your gun overgassed or undergassed?

Kian503

Joined Jul 2020
Posts 28
EE 0% (0)

OR, USA

Posted: 9/8/2020 6:23:45 PM EDT

[Last Edit: Kian503] [#49]

Quote History

Originally Posted By MeatAxe556:

OK, so weren't you saying that the Brown Bear 196 gr. subsonic load is the only round cycling reliably through your gun? The spent shells look fine.

https://www.k-var.com/ammo-brown-bear-762x39-196gr-fmj-500-rounds

Regular Brown Bear and GT 123 gr. have FTE issues and the shells come out mangled. Those two rounds have more than twice as much muzzle velocity and 3 times the muzzle energy as the Brown Bear subsonic round.

So what does that tell you? Is your gun overgassed or undergassed?

View Quote View All Quotes

View All Quotes

Quote History

Originally Posted By MeatAxe556:

Originally Posted By Kian503:
Behold! Here some spent casings friends. Silver steel is Brown Bear 123 gr that was causing the most FTE. The set with only 7 casings is 196 Brown Bear subsonic. Lastly I have pictured 124 gr Golden Tiger that caused the 180 degree failure I pictured above. I think that is the mangled casing you are seeing in the pic on the far left. Hope this helps. Also just a note not ALL the casings look like this. These are just the worst ones I could find after looking through about 300 rounds of empty. Also I tried to orient them in the pic so they are all facing the same way in my crazy mind.
https://i.imgur.com/jfuUxgv.jpg
https://i.imgur.com/7fdFOKK.jpg
https://i.imgur.com/lJiYMpb.jpg
https://i.imgur.com/wpAfuiZ.jpg
https://i.imgur.com/yro3qZq.jpg
https://i.imgur.com/IlS2XF1.jpg

OK, so weren't you saying that the Brown Bear 196 gr. subsonic load is the only round cycling reliably through your gun? The spent shells look fine.

https://www.k-var.com/ammo-brown-bear-762x39-196gr-fmj-500-rounds

Regular Brown Bear and GT 123 gr. have FTE issues and the shells come out mangled. Those two rounds have more than twice as much muzzle velocity and 3 times the muzzle energy as the Brown Bear subsonic round.

So what does that tell you? Is your gun overgassed or undergassed?

I did not say it was overgassed or undergassed. I said it was behaving like it is undergassed with the supersonic loads. The physics and engineering of these weapons is not under my full understanding so I would never make such a definite statement.

Hox

Member

Joined Apr 2012
Posts 1079
EE 100% (140)

OH, USA

Posted: 9/8/2020 6:55:08 PM EDT

[Last Edit: Hox] [#50]

I have some footage of mine malfunctioning, ill add it in here when I get the time. Timing of my slomo footage wasnt great (limited by my phone) so maybe Tim can take it and make some better use of the footage.

EDIT:
Top video nearly malfunctions on the slomo shot, then does malfunction on the next shot after the footage reverts to full speed.
Bottom video no malfunction but appears to nearly be so.

Footage below: