How did this happen?

[dennishoddy]

A friend that is very gun safe, took a newb to the range yesterday, for some pistol shooting. He had loose ammo in an ammo can for his 10MM.
The newb loaded his own mags, and while shooting, my buddy said the gun went off midway through the mag with a pop like a cap gun. It didn't cycle, so he recovered the gun, and ejected the spent round.
To his suprise, it was a 9mm that had somehow got mixed into the ammo can.
It was a center strike on the primer, and the brass fireformed to a 10mm.
It happened, but I'm at a loss to explain why. Cell phone pics suck.

 

[steak]

looks like it got in there just right to still go off, kinda scary deal. all that explosion and not getting the gas to explode in the right direction could have been bad.

 

[twss]

I've seen .40 go off in a .45 gun at a match.

 

[KurtM]

The rim of a 9mm and a .40/10mm are real close and what happens is the extractor hold the 9mm to the slide face of the .40/10mm and the firing piin does the rest. No danger here as there is no pressure being built up by the 9mm in the oversized 40/10mm barrel. same as a .40 in a .45. Matter of fact I demo this in my pistol classes and have shot at least 100 9mm rounds in a .40 and around 30 .40s in a .45. No big deal but it should point out that you got to KNOW what your putting in your gun!

 

[Glocktogo]

Kurt is right. I've seen this on numerous occasions and there's no danger or damage to the gun.

 

[aeropb]

Happens frequently at my job.

 

[aeropb]

Happened again today. This time catastrophically.

 

[dennishoddy]

Happened again today. This time catastrophically.

More details?

 

[Lance Jensen]

I've witnessed a LEO qualify with .357 sig out of a .40 Cal Glock

 

[TroyF]

I've witnessed a LEO qualify with .357 sig out of a .40 Cal Glock

Yep. Seen that too. Target ain't pretty. Kinda says something about how diffficult our qual course is huh?

 

[Lance Jensen]

Its like public school.... standards are set for the weakest link.
I've witnessed 9mm out of a .40 numerous times, but have never seen a failure.

 

[sefentress]

308's fire in 06's as well, it ejects looking a little like a rimless 4570 with a small crimp at the end.!

 

[Wall]

Its like public school.... standards are set for the weakest link.
I've witnessed 9mm out of a .40 numerous times, but have never seen a failure.

:sign0065:
I went to public school

 

[Robusto]

:sign0065:
I went to public school

Yes, you did.

 

[aeropb]

More details?

Top round of a 40 cal mag loaded with 9mm. Rest of mag loaded with 40. Mag inserted into gun. Slide worked. Extractor didn't grab the 9mm. 9mm went forward into the barrel. Click no bang, slide worked again. 40 cal round chambered. 9mm round pushed forward still in the barrel. Gun fired.

 

[dennishoddy]

Ouch! How bad did the person get hurt?

 

[Rodshoot]

Top round of a 40 cal mag loaded with 9mm. Rest of mag loaded with 40. Mag inserted into gun. Slide worked. Extractor didn't grab the 9mm. 9mm went forward into the barrel. Click no bang, slide worked again. 40 cal round chambered. 9mm round pushed forward still in the barrel. Gun fired.

Have had a running argument that this could happen if everything went wrong, due to loose fit of 9mm in .40 extractor. Argument over apparently.

 

[aeropb]

The person is fine. The gun however is completely fubar.

 

[jimeradams]

I have seen a .40 fired in a Ruger .45. I still have the case, it split open and made a strange noise when fired. Neither Ruger nor shooter were damaged.