Why you shouldn't cycle rounds multiple times

[sprigfan]

Got this in an email a while back at work. Not sure of the original source:

In September of this year a GCPD officer was involved in a situation which quickly became a use of deadly force incident. When the officer made the decision to use deadly force, the chambered round in his duty pistol did not fire. Fortunately, the officer used good tactics, remembered his training and cleared the malfunction, successfully ending the encounter.

The misfired round, which had a full firing pin strike, was collected and was later sent to the manufacturer for analysis. Their analysis showed the following: “…the cause of the misfire was determined to be from the primer mix being knocked out of the primer when the round was cycled through the firearm multiple times”. We also sent an additional 2,000 rounds of the Winchester 9mm duty ammunition to the manufacturer. All 2,000 rounds were successfully fired.

In discussions with the officer, we discovered that since he has small children at home, he unloads his duty weapon daily. His routine is to eject the chambered round to store the weapon. Prior to returning to duty he chambers the top round in his primary magazine, then takes the previously ejected round and puts in back in the magazine. Those two rounds were repeatedly cycled and had been since duty ammunition was issued in February or March of 2011, resulting in as many as 100 chambering and extracting cycles. This caused an internal failure of the primer, not discernible by external inspection.

This advisory is to inform all sworn personnel that repeated cycling of duty rounds is to be avoided. As a reminder, when loading the weapon, load from the magazine and do not drop the round directly into the chamber. If an officer’s only method of safe home storage is to unload the weapon, the Firearms Training Unit suggests that you unload an entire magazine and rotate those rounds. In addition, you should also rotate through all 3 duty magazines, so that all 52 duty rounds are cycled, not just a few rounds. A more practical method of home storage is probably to use a trigger lock or a locked storage box.

FURTHER GUIDANCE:

The primer compound separation is a risk of repeatedly chambering the same round. The more common issue is bullet setback, which increases the chamber pressures often resulting in more negative effects.

RECOMMENDATION:

In addition to following the guidance provided above of constantly rotating duty ammunition that is removed during the unloading/reloading of the weapon, training ammunition utilized during firearm sustainment and weapon manipulation drills, should also be discarded if it has been inserted into the chamber more than twice. This practice lessens the likelihood of a failure to fire or more catastrophic results.

[XDM45]

Got this in an email a while back at work. Not sure of the original source:

In September of this year a GCPD officer was involved in a situation which quickly became a use of deadly force incident. When the officer made the decision to use deadly force, the chambered round in his duty pistol did not fire. Fortunately, the officer used good tactics, remembered his training and cleared the malfunction, successfully ending the encounter.

The misfired round, which had a full firing pin strike, was collected and was later sent to the manufacturer for analysis. Their analysis showed the following: “…the cause of the misfire was determined to be from the primer mix being knocked out of the primer when the round was cycled through the firearm multiple times”. We also sent an additional 2,000 rounds of the Winchester 9mm duty ammunition to the manufacturer. All 2,000 rounds were successfully fired.

In discussions with the officer, we discovered that since he has small children at home, he unloads his duty weapon daily. His routine is to eject the chambered round to store the weapon. Prior to returning to duty he chambers the top round in his primary magazine, then takes the previously ejected round and puts in back in the magazine. Those two rounds were repeatedly cycled and had been since duty ammunition was issued in February or March of 2011, resulting in as many as 100 chambering and extracting cycles. This caused an internal failure of the primer, not discernible by external inspection.

This advisory is to inform all sworn personnel that repeated cycling of duty rounds is to be avoided. As a reminder, when loading the weapon, load from the magazine and do not drop the round directly into the chamber. If an officer’s only method of safe home storage is to unload the weapon, the Firearms Training Unit suggests that you unload an entire magazine and rotate those rounds. In addition, you should also rotate through all 3 duty magazines, so that all 52 duty rounds are cycled, not just a few rounds. A more practical method of home storage is probably to use a trigger lock or a locked storage box.

FURTHER GUIDANCE:

The primer compound separation is a risk of repeatedly chambering the same round. The more common issue is bullet setback, which increases the chamber pressures often resulting in more negative effects.

RECOMMENDATION:

In addition to following the guidance provided above of constantly rotating duty ammunition that is removed during the unloading/reloading of the weapon, training ammunition utilized during firearm sustainment and weapon manipulation drills, should also be discarded if it has been inserted into the chamber more than twice. This practice lessens the likelihood of a failure to fire or more catastrophic results.

Thank you.

[solidgun]

I feel that rechambering rounds should be covered in basic firearm safety courses. People are surprised when i mention the issues with doing this as no one has ever mentioned it to them.

[Humphrey Bogart]

Dang.

[Pat]

I admit thatI have been guilty of this practice. Thanks for posting and Happy Thanksgiving!

[sgruenhagen44]

i don't recommend using trigger locks on loaded guns. I have always considered setback as an issue but never the primer. Good post.

[fjrdc]

Also do not forget bullet setback.repeated chamberings can and will cause the bullet to be pushed back into the case causing increased chamber pressures IE; A possible KABOOM . There is a very good article in recent handgun magazine on just this subject ...

[jdege]

This is one of the reasons I always shoot out my carry mag, every time I visit the range.

I may do most of my shooting with cheaper, practice rounds, I may even shoot another gun, entirely. But I always shoot out my carry magazine.

I normally carry with a round in the chamber. I don't, normally, unchamber. I prefer to lock up my gun in its holster, rather than unload and/or unchamber. But there are occasions, now and again, where I do unchamber for some reason. And when I do, I end up rechambering.

I don't think that rechambering, once or twice or three times is likely to be a problem. But there are other problems that your carry rounds are exposed to - temperature changes, humidity, sweat, grease, oil, etc.

I don't think it's wise to carry the same rounds in your carry gun for more than a month or two, without switching them out.

[MNBlackjack]

I was guilty of this as well. I've actually noticed the setback problem from rechambering rounds and started shooting the carry mags at the range as well. The rounds that had the setback problem went into the misfire container at the range. I wish I would have taken a picture of how far the bullets had moved. It really freaked me out.

[zachkuby87]

This is one of the reasons I always shoot out my carry mag, every time I visit the range.

what he said... I figured that both the round may wear with some sort of ill side effect plus I always thought of it as a good thing to be used to the round i will be carrying on a daily basis. because I know I can tell the difference between cheap wolf ammo and my hornady +p they are almost different animals completely.

[tman]

I don't think it's wise to carry the same rounds in your carry gun for more than a month or two, without switching them out.

I've gone a year. More than once.

No issues.

[jshuberg]

I don't reload and have no idea, how much setback would be considered problematic for a 9mm round? I'm carrying Hornady Critical Defense, and the top 2 rounds are becoming tarnished, and it's been around 2 months since I've shot and replaced them. This is about when I would shoot and replace them.

I just measured them and one was setback .003", and the other .005". Is this considered to still be safe, or do I need to change my rotation schedule? Normally I replace the top 2 rounds when they start to become tarnished. It's an easy visual queue I use to remind myself. Rotating them every time I hit the range, which is around twice a week, I shoot and replace them around every two months.

Shooting my carry mag, or even the top round every time I hit the range seems incredibly excessive, and I've never even had a hint of a problem.

[aaron878]

I don't think it's wise to carry the same rounds in your carry gun for more than a month or two, without switching them out.

I've gone a year. More than once.

No issues.

Questions: Does your department issue you ammo for practice? If so, is it the same as your carry ammo? How often do you have to qualify?

Whenever I seem to buy once-fired brass it's always premium nickel plated stuff, always assumed it was from law enforcement agencies.

[tman]

Questions: Does your department issue you ammo for practice? If so, is it the same as your carry ammo? How often do you have to qualify?

Whenever I seem to buy once-fired brass it's always premium nickel plated stuff, always assumed it was from law enforcement agencies.

We usually have two range days per year. Sometimes we shoot up our carry stuff, sometimes we set it aside and load it back up afterwards. We have separate practice ammo.

And before the rest of you get worried that we don't shoot enough, we can usually grab at least one box of practice ammo a month and use our indoor range to stay sharp. Ammo availability sometimes depends on how well the firearms instructors communicate with the check writers....

[tizzo]

Thoughts on press checking and its impact on set back or primer separation?