I posted this at GlockTalk; someone suggested I post here (larger experience base here, probably). Sorry to come on board with a problem as my first post, but would like opinions or observations.
Day before yesterday I took a new .40 Shield to the range, along with some other firearms. The only .40 ammunition I had handy was an older box of HMR 180 gn. I don't care for HMR and don't buy it, but this had been on the shelf for some time. HMR uses mixed headstamps, reloaded ammunition, plated bullets from the appearance. This particular case was a Winchester.
When the case failed, it was about 25 rounds into the box, third round in the magazine. The shot felt unusual, and it vented into the mag well, and blew the magazine out. I was hit in the face with some debris, and my hand hurt in some places, and was numb other places. The case remained in the chamber, sticking part way out.
The bulging adjacent to the blowout marks the point at which the case was out of the chamber, which is to say that it couldn't have been fully in the chamber when the discharge/case failure occurred, as the demarcation between bulge and sized diameter is clear. Below are two pictures of the barrel, one with the ruptured case inserted as far as it can go, and the other with a loaded factory round inserted fully into the chamber.
My initial thought when examining the case was too much charge and a weak case, which raised two questions for me. One was whether the chamber offered enough support or could have allowed the case to rupture like that, and the other was why there were no high pressure signs on the primer (no flow, no flattening, etc). In the picture above, the bulge clearly occurred outside the chamber, with the bulge preventing the case from returning any further into the chamber. In the picture below, a factory round is fully seated, and appears to be well supported.
This appears to me to be either a round that fired out of battery, one that unlocked and allowed the slide to travel aft before chamber pressure dropped, or a situation in which a slam fire or similar case occurred with the primer striking the round outside of battery.
Are there other known cases of the Shield firing out of batter, and if so, what's the fix? I'm sure the HMR ammunition is a contributing factor (possible variance in the powder charge, the unknown regarding whether bullet set-back occurred, and potential for unknowns with the case in reloaded ammunition). However, it doesn't explain the lack of high pressure indications on the primer, or the way the case appears to have failed well out of battery.
Any thoughts?
Day before yesterday I took a new .40 Shield to the range, along with some other firearms. The only .40 ammunition I had handy was an older box of HMR 180 gn. I don't care for HMR and don't buy it, but this had been on the shelf for some time. HMR uses mixed headstamps, reloaded ammunition, plated bullets from the appearance. This particular case was a Winchester.
When the case failed, it was about 25 rounds into the box, third round in the magazine. The shot felt unusual, and it vented into the mag well, and blew the magazine out. I was hit in the face with some debris, and my hand hurt in some places, and was numb other places. The case remained in the chamber, sticking part way out.
The bulging adjacent to the blowout marks the point at which the case was out of the chamber, which is to say that it couldn't have been fully in the chamber when the discharge/case failure occurred, as the demarcation between bulge and sized diameter is clear. Below are two pictures of the barrel, one with the ruptured case inserted as far as it can go, and the other with a loaded factory round inserted fully into the chamber.
My initial thought when examining the case was too much charge and a weak case, which raised two questions for me. One was whether the chamber offered enough support or could have allowed the case to rupture like that, and the other was why there were no high pressure signs on the primer (no flow, no flattening, etc). In the picture above, the bulge clearly occurred outside the chamber, with the bulge preventing the case from returning any further into the chamber. In the picture below, a factory round is fully seated, and appears to be well supported.
This appears to me to be either a round that fired out of battery, one that unlocked and allowed the slide to travel aft before chamber pressure dropped, or a situation in which a slam fire or similar case occurred with the primer striking the round outside of battery.
Are there other known cases of the Shield firing out of batter, and if so, what's the fix? I'm sure the HMR ammunition is a contributing factor (possible variance in the powder charge, the unknown regarding whether bullet set-back occurred, and potential for unknowns with the case in reloaded ammunition). However, it doesn't explain the lack of high pressure indications on the primer, or the way the case appears to have failed well out of battery.
Any thoughts?
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