Sunday, October 12, 2008

A .40 Caliber Mystery

Shown here from left to right are 9x19mm NATO, .40 S&W and .45 ACP cartridges.

This is a Blazer 40 S&W round which was fired in my Glock 22. The shot did not feel right so I unloaded and benched the pistol so I could track down my "brass." When I picked it up from the floor it looked strange but it took me a few seconds to figure out why. The first thing I noticed is the extraction groove does not exist anymore. T

Then I noticed that about 1/3 of the way along the case moving away from the primer was a small swelling. This is a 40 S&W round that was cycled through a .40 caliber Glock 22. It is not a 9mm round. It was a factory loaded aluminum cased Blazer round. The visible scratches on the case are most likely from carrying the case in my pocket.

Another shot of the case.

As you can see the extraction groove is gone. Fro this angle the sidewall of the case looks straight.

I inspected my Glock before reusing and I could find no problem with the pistol. The brass .40 caliber ammo I used afterwards all functioned normally. I will no longer use any aluminum cased ammunition in any of my Glocks.

If anyone has had any similar experiences, I would be interested to hear about it.

Updated on 10/22/08:

Some nice folks on the Gunboards Forum at:
were kind enough to suggest I contact Blazer with my pictures and questions. Here is their response:

The Old Salt: what you discovered was a rare incident of the case missing the "head-turn operation" during case making. In this instance it is not a matter of the extractor groove not "existing anymore", there never was an extractor groove on the case. Since the round was fired in a Glock and it has a rectangular firing pin, look to see if the bulge in the case matches with the feed-ramp in the barrel i.e. 6 o'clock or 12 o'clock when looking at the rectangular firing pin mark on the primer. That would be my guess as to the reason for the bulge. The disconnector on the Glock should keep it from firing when the slide is not "in-battery" a safety feature built into the gun.

Pressure and velocity from the round should equal that of the other rounds in the box as they would have all been loaded at the same time, no safety issue.

Since the cartridge headspaces on the case mouth it went into the chamber properly. What I find interesting is there must have been enough lip on the back of the case that the extractor was able to hook the case and extract it. Had that not happened, the next round would not have been able to feed as the case would have remained in the chamber blocking feeding of the next round.

Sorry for the problem, does that explain what and how it happened?

Shoot Straight!
2299 Snake River Ave.
Lewiston, ID 83501
Sr. Technical Coordinator
(866) 286-7436

Larry The Cable Guy Says, According To MY E-mail:

A day without sunshine is like night.

On the other hand, you have different fingers.

42.7 percent of all statistics are made up on the spot.

99 percent of lawyers give the rest a bad name.

Remember, half the people you know are below average.

He who laughs last thinks slowest.

Depression is merely anger without enthusiasm.

The early bird may get the worm, but the second mouse gets the cheese in the trap.

Support bacteria. They're the only culture some people have.

A clear conscience is usually the sign of a bad memory.

Change is inevitable, except from vending machines.

If you think nobody cares, try missing a couple of payments.

How many of you believe in psycho-kinesis? Raise my hand.

OK, so what's the speed of dark?

When everything is coming your way, you're in the wrong lane.

Hard work pays off in the future. Laziness pays off now.

How much deeper would the ocean be without sponges?

Eagles may soar, but weasels don't get sucked into jet engines.

What happens if you get scared half to death, twice?

Why do psychics have to ask you your name?

Inside every older person is a younger person wondering, 'What the heck happened?'

Just remember -- if the world didn't suck, we would all fall off.

Light travels faster than sound...that's why some people appear bright until you hear them speak.

Life isn't like a box of chocolates. It's more like a jar of jalapenos. What you do today, might burn your butt tomorrow.