Getting nasty failure to eject on every round fired.

Most times, the fired case doesn't even make it out of the ejection port, and gets jammed up when the bolt tries to strip a round from the magazine.

Occasionally I'll get a stovepipe in which the casing is wedged in the front of the ejection port, and is not held in place by the bolt closing on the fired case.

What makes this issues especially peculiar to me is that I've had this gun for a while and have fired all kinds of steel cased and surplus ammunition.

I rotated through 3 different mags, and all 3 had the same results.

My buddy has a DPMS Recon (G1), who was shooting beside me, and his gun loves the ZQI...no problems whatsoever.

My gun is 100% with all other ammos, but is worthless when fed ZQI...What gives??

To make things worse, I've hoarded over 1500rds of this shit...

UPDATE 1:

Ok, so I decided to buy a new midlength barrel. AIM Surplus had the Losok barrel on sale, it got good reviews, so I bought it.

It came in yesterday, and I'm trying to have it installed today.

Link to Losok Barrel

UPDATE 2:

Got the new barrel and rail installed today, and the headspacing checked out A-OK.

However, there is a miniscule heigth difference between the new rail and the receiver rail. Meh, i paid $60 for the rail and got a $60 rail... its nothing fancy, but works.

I also bought an Ares 308 NiB bcg today for $149 shipped off of slickguns today... havent seen that deal since last Christmas.

Here is a pic of the newly outfitted stick. Range report as time allows.



RANGE REPORT 1:

The range trip did not go as planned. Jammed within the first 3 rounds.

I brought 60 rds of ZQI and 3 different magazines.

The results were the same as before. However, this time, it frequently failed to pull the empty shell from the chamber. Also, the ejection pattern was weak and sporadic when the shells did manage to make it out of the chamber.

I also noticed that there were hardly any extractor claw marks on the brass...

The brass did not seem damaged, nor bulged or damaged primers, etc, etc, etc...

After doing more investigating, Im thinking the problem may be a faulty extractor due to a shitty diet of 98% steel cased Tula for the past 8 yrs.

I don't think the worn extractor is handling the switch to brass very well...

Last week, I ordered an Ares NiB bcg which should arrive in the next few days. This should help determine if the current bcg is the source of the problem.

I have also contacted DPMS and they stated that they will send me a new extractor assembly (spring, etc) free of charge.

Updates and range report when the parts come in.

Thanks to all who are following and have added their input.

On a side note, I was able to sight in my scope, and the barrel seemed to be pretty accurate.

Once I get this thing up and running, Im confident that it'll prove to be one bad ass pill pusher!

Where does your brass normally land? If it's 1 or 2 oclock when feeding normally than you are cycling pretty fast.





What you describe sounds typical of overgassing. That ammo just might be a tad more powerful than the rest (I don't have any experience with it). Could also be a weak extractor on the bolt, perhaps just in the context of hot ammo.





A heavy buffer might fix you right up. After that, adjustable gas block. Get your brass landing at 3-4 o'clock.




BTW, if you have any thoughts of an adjustable gas block then don't bother with the heavy buffer. Reducing gas will take care of that.




-Stooxie

 

I'll bet you don't have an adjustable gas block, do you?

I shot some in my DPMS GII thought I was shooting black power gun! No more for me.

I'll you ya, V....the smartest thing I ever did was listen to you guys about using an adjustable block on my Mega.  Working on getting my roomie into an adjustable block on his ArmalLite.  It runs great until you put a can on it and then things get a bit ugly.



OP:  I see a LOT of people who don't have issues with other ammo...but the minute they put ZQ in their guns...it's choke city...so you are definitely NOT alone.



 

The ZQ actually works good in my recent 308 build, BUT I do have a syrac adjustable gas block, had to tune down the gas specifically for that ammo

Another possibility is a chipped or worn extractor, and it just happened to show up when you started shooting the ZQ.  If you don't see anything wrong with the extractor, try one of the extractor tuning, or plus up kits, or whatever they call them.

According to another thread DPMS and Bushmaster extractors seem to be a problem a child.

I shot 4 or 5 boxes of that ammo in an AR15. Receiver inside looked like a wood burning stove, even the exterior around ejection port. Never seen such a filthy ammo so no more in any caliber.

I had to open the gas port to .076 on my LR 308.
It was .070.  
It runs on ZQI but it doesn't shoot it accurately.

Thanks for the replies...

So basically, I'm hearing that my gun is possibly overgassed?

Is ZQI really that high pressured compared to surplus ammunitions?

Guess I'll start looking into adjustable gas blocks...

What exact DPMS 308 do you have?  You didn't provide any details of the gas system length, gas block type, lubrication, etc.

If it has an aluminum gas block, this would make a lot of sense, as they will last for a little while, then fart spray the bed as you describe, with a lot of FTEject/Stovepipe.

Is this a carbine or rifle length gas system?

Pics would help.  Also, inspect your bolt for any damage to the extractor.  These rifles are known for having a fairly high % of extractor problems, weak metallurgy, and broken or deformed lips under fire.  I had one on my 1st LR-308 right off the shelf.  That was the last factory rifle I ever bought, as a matter of fact, in 2006 or 07.

I shot some zqi this morning after my trip to Walmart last night for some cheap basting ammo for my dpms 308.

This ammo is violent that's for sure and ejects at 1 o'clock. And I even had some eject almost straight forward. My hunting and precision ammo shoots soft and ejects around 3 o'clock.

I'm also running a can so it doesn't help the matters any.

Sorry about the lack of details... i do not have pics of the malfunction.

The gun is a DPMS LR308 AP4. 16" barrel with a carbine length gas system. The gas block is the factory A2 style front sight type.

Im lubing the gun with Militec. I am also running a suppressor, however it didnt matter if it was on or off because its 100% failure with ZQI.

I dont think i have any broken parts as i was shooting Tula with no problems after the ZQI refused to run.

I had a little that I was planning to just use in my FAL, but since I was out and running a chrono with my DPMS, I figured I would try it out.  No malfunctions at all, and it was one hole accurate at 100y, I was shocked.  I dumped 5 rounds over the chrono and the velocities were VERY consistent:
2731
2738
2743
2744
2746

Someone else can do the math, but them's some decent velocities out of a 16"bbl

I've had some batches that were like this... And others that were WAY underpowered, like 2,400-ish.

All of these were in the tannish boxes and head stamped 13.  I also had some white box that was head stamped 14 that was also GTG, but I didn't write down the numbers because they were mostly the same...

So CLGS 7.62 NATO with a suppressor is a really harsh configuration as-is.  Makes sense that it would run on Russian under-powered ammo, since the burn rate curve would be more optimal for the excessive amount of dwell time you have.

You basically have a very heavily-gassed carbine with port pressures that exceed the design parameters of 7.62 M80, which was meant to drive the M14 gas system with much less port pressure.  The AR10's RLGS was engineered around M80 and the port pressure window it produces at that location in the barrel.
Stepping down drastically to a CLGS based on AR15 carbine handguard lengths never made any sense at all to me in these guns.  If you look back at the evolution of the AR10 in the 1950's, the prototype Dutch AR10 carbines, the pre-ban SR25K, and the ArmaLite Inc. (Eagle Arms) AR10 carbines, they all use a Mid-Length Gas System of some type, and this choice of gas system length was based on known burn curve shape and pressure of the 7.62 NATO.

I personally think that 16" CLGS with a full-powered 7.62 NATO or .308 Win. load is way outside of sanity when you look at the dwell time.  It causes violent, early unlocking, which is extremely harsh on extractors and brass, as well as the recoil system.  Add a can into the equation, and it only makes it worse.

I need to make sure its a carbine system...

Short of rebarreling this gun, what can be done to fix/ mitigate these negative effects?

Try one of those Slash heavy buffers, that's the easiest way. Not cheap, though, unfortunately. Next step is something like this:



http://www.midwayusa.com/product/413559/jp-enterprises-adjustable-gas-block-with-a2-front-sight-ar-15-lr-308-standard-barrel-750-inside-diameter-stainless-steel-matte



Again, if you are inclined to go adjustable then skip the heavy buffer.



The other way is to not use that ammo and stick with the stuff that's working. Might sound silly but if everything was working fine before then you know where the sweet spot is.



-Stooxie



 

Not a surprise.  I happen to like ZQI in 7.62, 5.56 and 9x19, but it is definitely warmer than most other plinking ammo, very noticeable in 9mm handguns.  But I can't recall a single failure with the M80 in my 18" .308 AR, 16.25" DSA FAL or my Century G3.  Accuracy has been typical of ball ammo, though.

If it's an AP4, it has a CLGS.  I really suspect that the decision to make the DPMS Carbines in .308 with a CLGS was not based on any testing or logic.  It makes no sense at all.




KAC SR25K for comparison:




Aside from a barrel change and upgrade to MLGS, I would look at springing and buffering it up, as well as dialing down the gas.   If you get an adjustable gas block, make sure it is steel, not aluminum.

You can solve all your timing problems with an adjustable gas block, and IMO should avoid buffer modifications.

I never had the issues you describe, but I put one on my Oracle. I can crank down the gas system and get 168gr@2600fps handloads to trickle out of the ejection port. I then open it back up and get 110gr@1800fps handloads to cycle with 100% reliability.

Also, all the ZQ1 I have chronographed was likewise in the low-2400s range.

How wet are you running the bolt with lube? I run mine glistening (almost dripping) wet with motor oil and often go 500 rounds without cleaning--and that is only a limit I set myself because I start feeling bad about it.

My experience with ZQI is that it is dirty as hell and inconsistent ......some rounds seemed hot and others seemed under powered ...........I just bought a bunch of it until I got my reloading dies.........Ive reloaded a bunch of it and the brass in fine.........I use Hornady 150 grain bullets and 46 grains of Winchester 748..........runs fine in my PSA PA10

I run a 16" with intermediate length gas and a carbine receiver extension and an adjustable gas block (Syrac). Your results seem typical to what I and others see with short barrel/carbine RE setups. I also run a heavy buffer and disagree with the notion of trying to change dwell/timing with gas alone. It's simply not as effective. Running a suppressor exasperates your problem also. I see my 308 as being much more ammo finicky vs any 223/5.56 build. YMMV

ZQI is made in Turkey, so lot to lot variation is all over the map.



I agree that approaching insane over-gassing is probably best done from these two angles:

* Adjustable gas
* Buffering and springing

Same.  Century L1A1 which works perfectly, had to keep adjusting the gas every five rounds or so.  Green box ZQI from Wally World.  Nowhere near as consistent as the Hirt I still have or even the CAVIM (pre Chavez stupidity).

Do not tweak your rifle based on ZQI ammo malfunctions.  It is range noise fodder.  Use your handloads you trust or first quality major manufacturer stuff and understand the tolerances it's manufactured to.  NATO 7.62 ball has a pretty wide acceptable range compared to, say Federal Gold Medal Match.

Update in OP...

Anbody have any input on Losok barrels?

So everyone tells you your gun is overgassed and to get an adjustable gas block and/or a heavier buffer .... and you ignore them all and instead buy a new barrel?

I actually recommended getting a barrel with a MLGS, because CLGS just doesn't make a lot of sense in a .308 gas gun of this type, no matter how many of them have been manufactured.

OP:  What handguard are you going to use with this now?

I chose to go the barrel route because I felt it was the only honest fix... Everything else was a band aid....Yes, adjustable gas blocks are cool and useful for suppressed fire, but I want my gun to function without band aids in a barebones configuration.

As far as handguards go, I will be using the Guntec 12" rail seen here

Adjustable gas blocks are almost required if you want a 308 AR to run with all types of ammo. You mentioned a suppressor too and that only makes it worse. Go ahead and pick up one of these: http://www.joeboboutfitters.com/SLR_Sentry_7_Clamp_On_750_Premium_Adjustable_Gas_p/slr-sa7-cm.htm

7.62 ZQI is underpowered. My SR-25 barely cycles it and will short stroke now and then on this stuff unsuppressed, and functions fine with a suppressor mounted. I doubt you're overgassed. I wouldn't go buying a new barrel to solve a shitty ammo problem. Get some LC and give it a try before spending big bucks on a new barrel.

It's already a done deal. Barrel is being installed in a few hours...Range report within next few days as time allows.

I disagree with this.  Proper location and size of the gas port, sealing of the gas port, and optimum suppressor baffle arrangement will allow suppressed and unsuppressed without adj gas.

I submit the KAC SR25 ECC as evidence to that effect.  Only one of my 5 AR10's/LR-308's had adjustable gas, and it wasn't necessary.

Now, with MLGS/18" suppressed, there might need to be something to tame that dwell and back pressure, so I wouldn't rule it out for this build.  If I were doing 18" .308, it would have RLGS with a sealed gas block, sealed gas tube, optimum port diameter, and fed only one of a few types of loads using quality, brass-cased ammunition.

So you bought a barrel to try and fix an ammo issue, even though there's no way of knowing the new barrel will work with ZQI either?

Im gonna be a sad panda if the barrel doesnt solve my cycling problems.

I am def open to adjustable gas block, but only to achieve optimal gas regulation...NOT to solve normal cycling issues.

Why are you stuck on ZQI?  And if that's the case...sell the AR and just buy a PTR-91. They'll eat all sorts of junk ammo.

CLGS/16" .308 is an issue before you even shoot it, unless it's sole purpose is an occasional plinker or internet pic tool.

Gas port pressure with CLGS/.308 is off the charts form what it should be.

Update with pic in OP

Update in OP

If your rifle is that old then it is a "high profile" receiver. Often referred to as a .210" tang height (the tang being the top/rail portion of the upper that overhangs the charging handle). The rail you bought is for a newer style .150" tang, so you are going to have about a 1/16" of mismatch. I believe it was changed (this time..) in ~2010.

Did you add an adjustable gas block?



A refreshed extractor might solve your immediate issue. If your brass is ejecting successfully but violently you might still want to consider a heavier buffer or adjustable block.



-Stooxie



 

Took my youngest son to the range a couple months back with my Armalite Retro and he put 30 rounds of ZQI 100 yards out with iron sights. First time he ever shot it. All in six inches, most in four. No ammo issues. I was quite impressed.




Stepped out to 200. His eyes are worse than mine so I spotted for him on the left target. One high left, one low left and eight grouped pretty nice. I shot five on the right target.