Debris blasting out of the rear of my CZ Omega

[RNA]

Alright, i just finished up with a 1500 rd supply of LAX reloads. Shot it through a Glock 17, CZ PCR, CZ 75 Omega and XDM full size. About four times while shooting through my CZ Omega, i got hot gas and debris through the rear splattering my face.

There is a sizeable gap in the rear of the gun where the ejector fits as the slide moves rearward, and I'm guessing that's where is coming from, but what's causing it?? I'm on the verge of getting rid of the Omega due to not trusting it in an emergency situation if i don't have time to grab glasses. Anyone else run into this problem? I keep my guns cleaned immaculately with just the lightest layer of clp for lubrication.

[Winkel]

I've had the same thing happen a couple of times with Perfecta ammo.  The next time it happens, try and find the ejected shell casing.  In my case, it failed to eject.

Both times, the casing showed signs of being under charged.  The primer didn't flatten out and the casing was fouled from gasses escaping backwards.  I checked the barrel to make sure it wasn't a squib and it was fine.

I attributed this to a light powder charge.  I believe it didn't allow the case to properly expand and seal the chamber.  I highly doubt this is because of the gun but would welcome other ideas or opinions.

Winkel

[bang bang]

If you put bad gas in your car/truck are you going to get rid of your vehicle???

Before you do anything, take a breather and examine the ammo.  Don't forget the gun is only part of the equation.  You, the shooter, the gun and then the ammo are all in the  group.  Chances are its not you, but look at what the above poster mentions.

worse case if you dont feel its the ammo, give the gun a good cleaning and then buy some factory ammo and see if you get the same results.

[bugboy]

I agree, buy some quality factory ammo and see how it goes.

I'm not familiar with LAX reloads as I only shoot my reloads or factory ammo.

[1SOW]

i got hot gas and debris through the rear splattering my face

Strange problem for sure.  "4 times" out of how many rds fired in the Omega vs the other pistols.?
Where at the "REAR"?  Does it show some signs of that debris/crud?  Was there any carbon/sooty buildup? 
Did any LAX rds fail to feed fully in the Omega?  Was there any buildup at the ejection port or around the mag well?

While I agree with the others about trying some factory ammo,  the fact that the CZ PCR, Glock or XD 'didn't' show any noticeable problems with that ammo is problematic.  Were they particularly dirty after shooting the LAX ammo?
 

[Longshanks]

"  the fact that the CZ PCR, Glock or XD 'didn't' show any noticeable problems with that ammo is problematic " ..... well no not really , because they are designed diffferently and propably do not have a gap on the rear ... just thinking out loud here.

[coolbox]

Had a similar problem some years ago with reloaded ammo, once. IIRC, It was attributed to overcharged round, the primer punctured and gases came out backwards...or something like that. It came out from firing pin channel. The result (blow back through the fp channel) would be almost identical in any hammer fired pistol.

[SI VIS PACEM PARRABELLUM]

As some others have stated try some good quality ammo before you give up on the gun. I've been reloading for 25 years and I've run into debris issues like this with certain powders before. You can get flying flakes of unburned powder in loadings that don't ignite properly. Also some reloads may not ignite properly if the bullet isn't crimped securely enough as can be the case when reloading brass produced by multiple manufacturers.

[Ragnarok]

Yeh...reloads. They are what they are. I've had it happen with other pistols. What happens is you get one that's either loaded a bit light..or just doesn't expand and seal-off the chamber like it should. Gas and un-burned powder comes back past the case through the chamber.

Look at your empty cases and see if some are black on one side...that's caused by gas and crud leaking by the case. Lighter loads are the usual cause. These just don't seal-off well and may not burn up all the powder.

[Stuart]

certain guns, certain powders.
it can happen. try a different ammo and see what happens.

[Ragnarok]

Just going to add that I just got a 75B Omega not long back. Has been working absolutely perfect with a variety of ammo. However the only reloads I've used are my own which ain't nuthin' special...but the bullets are crimped tight and Unique burns reasonably clean.

I've had budget factory new ammo that leaves so much loose/unburned powder in the gun and on me that it makes a guy wonder about the possibility of a secondary explosion! Can get a tea-spoon full of powder out of the gun..and off your shirt..and off your glasses and face! 

The Omega really rocks with the Winchester 'Nato' 124gr ammo..did well with S&B 124gr...Israeli 124gr hp and Winchester 147gr hollowpoints too...like it was made for the heavier weight of bullets. The 115gr stuff(hollowpoints and ball) do well too..accurate enough, however it seems like the bigger bullets print perfect to the sights.

[rhart]

My face gets splattered if I over lubricate a gun...

[zmr]

You should know better than to shoot somebody else's reloads.

Well, now you know. And knowing is half the battle!

[RNA]

Hey guys, to answer a few questions:

-Gun was cleaned prior and lubricated IMHO perfectly. I tend not to over lubricate because I live in Las Vegas and seek to avoid having excess oil that can gum up with dust

-There was no buildup or caked on crud ANYWHERE prior to the last session in question. In fact, my guns are all clean as a whistle when I take them out. I'm a bit OCD and pride my guns on being clean and ready for action.

-There was no irregular crud built up afterward, either. Looked like a normal range session.

-It very well could be the reloads being under- or overpowered. Both explanations sound reasonable. Either way, though: it's the design of the relatively open slide rear end that's the problem. Since I shot that stash of reloads between 4 guns (with preference toward the Omega) I would say those instances of blowback were all within about 400-500 rounds.

I totally appreciate and understand the advice that everyone gave about buying quality factory ammo. For what it's worth though, LAX is respected for the quality of its reloads and is considered GTG by many shooters. The problem, like I said, might just be the design of the Omega. Even if they were lousy reloads, I didn't get the potentially debilitating blowback in my CZ PCR, Glock or XDM that I got from the Omega. Suffice to say, in the beloved SHTF scenario, I would grab the Omega last of the bunch because who knows if any scavenged ammo would be quality or not.

At any rate, it's a moot point: I sold the Omega to my buddy to take advantage of a deal on an SP-01 on Cyber Monday. There's more tuning potentially on the original trigger system anyway, but the more closed off slide rear end is a definite bonus in my mind. I fully disclosed the splattering with the reloads and advised him to buy quality range ammo instead of the reloads I've been using. Thanks again for everyone's input!

[Rmach]

Is there a difference with the rear area of the slide between the Omega and the regular CZ75b?  I know what you mean about burnt powder blow-back because I sold a Taurus PT-809 that threw powder back in my face too many times with factory new ammo. I have 300 rounds through my new matte stainless 75b, and there is no hint of any powder blow-back.