Kaboom! - Almost ?

[flyinverted]

Background:

I have been reloading for about 20 years. Never any issues with my ammo.
About 15,000.45ACP rounds loaded, 10,000 9mm rounds loaded.
New to 40 SW and familiar with the high pressure

This was a reload
5.3 grains of HP38. 165 Grain RNFP Plated Extreme bullet.
Winchester brass.
Winchester standard primer
OAL set to 1.135 in

What happened?
This was one of the first 100 of the 40SW reloads I did, and somewhere around round #50 shot in my G23.

The shot was normal as I saw a hole in the paper after I pulled the trigger.
The experience was not normal as I didn't feel as much recoil and I'm 99% sure the slide did not cycle. I manually cycled the slide, and this is the brass that was ejected.

Here is my suspicion on what happened.

1. In the bottom photo you can see the mouth of the case is dorked.
That was from the initial setup of the flaring and was obviously too much for the seating die where this dork took place.

2. The imperfection of the brass prevented the round from fully entering the chamber.

3. While not in full battery, the gun still fired while not fully supporting the case. (This doesn't make sense as 3/5 of the case is about the size of a .45 acp case and not a 40SW case.

Note:
There was no hot gas released on the outside of the gun
There was no "kaboom" as seen on other internet threads
There was no fouling of the magazine, or magwell.
Subsequent rounds fired fine.

I'm temped to now have the barrel tested for cracks.

Your thoughts?
*** UPDATE ***
The answer has been identified and accepted as a .40 in a .45 barrel. Thanks

[cwilliams]

Is that for certain a .40 S&W case?

Check out this page that has something similar to what you experienced - http://www.tannersgun.com/glock-19-g...dangerous.aspx

To me it looks like you ran a 9mm case/round through your gun. The pictures on that page look exactly like what happened in your photo.

[orangeusa]

Compared to you, I am a noob. Is it possible that brass was defective?

Your powder, bullet ect seem well within guidelines.

And yeah I would try some of your rounds through a rental 40...

HECK : I am in N. OC. You want to borrow pistola or rounds? I have some 40 cal Berettas.

.

[Zamble]

I agree. The brass looks like a 9mm. I had one look exactly the same when a 9mm got mixed in the .40 I was doing in my 1050. I didn't see it until it was resized.

[Cokebottle]

Is that for certain a .40 S&W case?

Check out this page that has something similar to what you experienced - http://www.tannersgun.com/glock-19-g...dangerous.aspx

To me it looks like you ran a 9mm case/round through your gun. The pictures on that page look exactly like what happened in your photo.

Ditto.
First thing I thought was a 9mm round slipped into the batch.

This is the primary reason that I have only 9mm, 45, and 357.
More than once we've read stories where someone's range partner picked up the wrong mag.

[flyinverted]

No not a 9mm case. It is stamped Winchester 40 S&W
Rim measures at .418
Butt measures at .424

That is a 40S&W case

[orangeusa]

You want to borrow a 96 and see if it's your gun or rounds?

I even have some OMG (reloads) we could try..

It seems as if it fired out of battery or the shell couldn't have expanded that much..

PM if interested.

[cwilliams]

No not a 9mm case. It is stamped Winchester 40 S&W
Rim measures at .418
Butt measures at .424

That is a 40S&W case

Now I'm stumped.

Every photo I could find of an out of battery firing of a .40 shows the case expanding at the base and not the mouth.

Here's another instance that has brass that looks just like yours. Sure enough, 9mm through a .40 gun - https://www.ar15.com/archive/topic.h...5&f=4&t=112101

And here's a .40 in a .45 gun - http://looserounds.com/2013/12/17/40-in-a-40/

If you didn't continue to shoot that gun I would be thoroughly inspecting for a chamber failure.

[Cokebottle]

Can you post a shot of that casing next to an unfired 40, and a 9/38/357/380 if you have one?

Agreed that if it fired out of battery it should have bulged the base. To expand all the way out at the lip, it would have had to have had only the boolit chambered.

[flyinverted]

Left to right
38 Special, 9mm, Once fired 40, bad 40, .45 ACP

[John Browning]

The only answer that is physically possible is that you fired a .40 in a .45. I have shot a .32 in a 9mm, looked the same.

[orangeusa]

That flare is bigger than 45. And split.

[stilly]

Is that for certain a .40 S&W case?

Check out this page that has something similar to what you experienced - http://www.tannersgun.com/glock-19-g...dangerous.aspx

To me it looks like you ran a 9mm case/round through your gun. The pictures on that page look exactly like what happened in your photo.

Yeah, what does the case head show on it? Caliber? This was my thought as well based on what I saw.

You know what happened...

You picked up a .40 that was resized to 9mm specs on accident and possibly trimmed too, you loaded it since it said .40 on it, then that happened...

I have a .357 sig that says .40 on the base.

I aint surprise with all the things that these presses can do. They are strong and tend to push brass around with no issues.

Unless of course your barrel is a .45 barrel or it was already jacked (Fire Dragon barrel?) and allowed the brass to swell up that much... Heh. I still say to show pics of the base. I wanna see the headstamp!

[flyinverted]

[stilly]

Hmmmmm.

Interesting. - I am gonna go with the 40 resized as 9mm.

HEY wait, have you checked all of your other ammo? SOMETHING is just not right here. Either that shell was resized too small (as in .380/9mm too small) or that barrel is ****ED UP. Specifically the CHAMBER. But if everything ELSE shot fine, then how could it be the barrel? Which points me back to the brass/ammo.

Ahhh. OKAY. So let's suppose you have a NORMAL reloading yadda yadda going, and the brass was NOT resized incorrectly (could have been a previous reloader's brass resized to 9... JUST SAYIN!) but instead, the gun decided to shoot, or you possibly had a slam fire with only the bullet and a tiny bit of the case inside the chamber. I can see that happening.

Okay, based on this new evidence, I think you had it correct in that the round FAILED to chamber all of the way because SOMETHING prevented it, like a flared case mouth or maybe even something stuck in -hmmm- well, a poorly flared case mouth that was not closed all of the way could certainly all ow the bullet to go into the chamber without the case being able to follow, and the glock somehow slam fired or SOMEHOW was able to fire and as a result the case bulged and split. I would look at the magazine and see if there is any signs of gas cutting down in the receiver. Perhaps the case was supported on the bottom, but not on the top and sides and that allowed the case to swell like it did and split with the pressure. BUT, also, because of the way the SPLIT is Oh hold on a second here...

Have you tried to put that brass in your resizer after this happened? I wonder if this was a previous GLOCKED piece of brass and when fired, it had a WEAKENED side from the previous BULGE that was BUSTED. and (follow me closely here) it ended up splitting the case there and because the round was inside the chamber, it expanded the brass enough so that when it was manually cycled, it was able to expand and look the way it looks like it does now. One thing about split cases is that you can not resize them very well and they are very springy.

Hmm, check your other rounds and go shoot them and see if it happens again...

Oh and all glocks are evil and garbage now. Thank you OP for posting this evidence for the glocked files...