Reminder

[500KV]

This bulletin is from 2007 but the message is still relevant.
It's something that most of us are probably guilty of at times and the subject doesn't get a lot of coverage.

I do check the overall length of my carry rounds periodically, especially if I have reloaded the magazines a few times.
It may escape the notice of new shooters as well.

Just thought I'd throw it out there as a reminder.

Quote:
The following bulletin was received from the New Jersey State Police - Officer Safety Division

Date: February 23, 2007

Continuous reloading an chambering of the same round may cause catastrophic failure in semiautomatic handguns.

The Security Force at the Los Alamos National Laboratory in Los Alamos, New Mexico, recently reported on the catastrophic failure of a semiautomatic handgun when it was fired. The internal explosion caused the frame to break while the slide and barrel separated from the weapon and traveled down range. No one was injured in the incident. An investigation revealed that security personnel were repeatedly charging the same round of ammunition into the chamber.

Technical personnel at Glock Inc. advise that repeated chambering of the same round may cause the bullet to move deeper in the casing, further compacting the propellant. When a normal cartridge is fired, the firing pin hits the primer, igniting the propellant. When the propellant burns, the gas pressure drives the bullet out of the case and down the barrel. However, if the propellant has been compact, the pressure may increase beyond the gun's maximum specifications, causing the weapon to break apart.

Sigarms Inc's personnel confirm that reloading the same round five or six times will cause the problems, noting that reloading the same round even once will void their warranty.

Both manufacturers stress that the problem is not with the gun, but with chambering the same round repeatedly. The NJ Regional Operations Intelligence Center urges all law enforcement officers not to chamber the same round when loading their weapons.

[pacific nw guy]

holy crap

that is such an important fact. I had been practicing loading the chamber and used a round over and over. I acutally noticed the bullet was a bit scratched up and wondered if it could cause an issue.

has anyone here ever had this happen?

[mr surveyor]

the infamous "kaboom" has been documented numerous times and been traced to "bullet setback" on many occassions. Those that unload and unchamber their carry weapons daily are the most prone to have these issues. Personally, I rarely clear my carry weapon until I'm ready to clear it at the range by firing.

Every time you chamber a round it takes a beating on the feed ramp, and each time you rechamber the same round you risk pushing the bullet further into the casing. When that bullet gets pushed far enough into the casing the round itself becomes over pressured and can cause a catastrophic failure, resulting at the least an extra loud bang, or a magazine blowout (for those of us that might tuck our pinkie under the mag base that could result in a real problem), and at worst a barrel/frame failure and possible severe personal injury to the shooter or a bystander.

If you are in the camp of those that frequently unload your carry weapon, keep count of the number of times you nreload the top round and take it out of circulation at least weekly.... or better yet stand it up beside a fresh from the box factory round and check for overall length.....or use calipers to check for overall length compared to a fresh round. Personally, I think any perceptable bullet setback is too much and don't have any reason to unload/reload my carry weapon daily.

Be safe

surv

[Raoul]

We went to the range last week and a buddy actually noticed this with 2 rounds of Hornady JHP. It always pays to be alert.

[Bawanna]

Top Round

As the armorer for a police agency I've encountered this frequently. I have a box of duty ammo set out for both rifle 223 and pistol 45 and we encourage the officers to check visually any cartridge they have chambered and if the slightest doubt replace the questionable round with a new one. I personally inspect my own and rotate the magazine stack periodically so the same round doesn't take so much abuse. (I'm much poorer than the dept) A couple weeks ago I experienced the opposite. An officer came to me and said he found an empty case in the chamber of his backup gun (a Glock 30) and his gun was full of glitter!!!! I was at a loss till I saw the gun and knew right off that the glitter was gun powder (he'd never seen it before). The bullet had worked loose, apparently got caught by the rifling and pulled out when he cycled the slide. Funny now but I still have nightmares of what may have happened.
An excellent reminder for everyone here. Thanks for the reminder.

[mr surveyor]

just a suggestion to Admin....

This thread would be and excellent candidate for being renamed something like "Bullet Set-Back Discussion" and made a "Sticky"

There's a world of folks that probably are totally unaware of the issue, and potential for a catastrophic failure of the firearm's mechanical intergity.

again.... just a thought


surv

[Wayne's World]

MAN !!! .... I love the info on this site.
You guys are awsom.
Thank you.

[Fenderman]

Great thread defenitly a Sticky candidate!

[jocko]

another reason to fire all the rounds in your carry magazine at least once a month or more often. Error on the side of "safety" That bulletin is a "norm" to most all shooters though, so not sure it needs to be a sticky..

[johnatw]

Is there a rule of thumb about this? Or should any ammo with a detectable shortning be discarded?

[500KV]

Is there a rule of thumb about this? Or should any ammo with a detectable shortning be discarded?

If you're set up to reload and don't want to discard the round you can do the following:
Use a bullet puller to "slightly" pull the bullet, re-seat to the correct length, and taper crimp it.
I do this if I find one several thousandths out of spec.
Seems like a lot of trouble I know but works for me.

Otherwise you just need to chunk it.

[zena]

Is there a rule of thumb about this? Or should any ammo with a detectable shortning be discarded?

When in doubt, throw it out. Or as mentioned above, pull and reseat/crimp. It's only one round. Hands, eyes, fingers and friends are much harder to replace.

[wyntrout]

Along that line... Back in the 70's I had a Dan Wesson .357 and at least one S&W, as well. The cylinder chambers on the DW were so tight that I couldn't get reloads into them while they dropped right into the S&W... so, I just ran them through the carbide sizer to the depth of the bullet and then they worked fine. I like cannelured bullets and crimping. The combination should help prevent setbacks. With magnum loads you could have "set-forwards", which could stop cylinder rotation if you're real sloppy in reloading.
Wynn

[jocko]

absolutely, life is to short to weaste on a 50 cent round...

Not sure now I said it should not be, that maybe this would be a nice sticky. Lots of new owners come and go here and I myself have been guility of ejecting a defense round only to again reload it and move on, when common sense says not to do it...

[wyntrout]

FTFs really scare me. I hold the gun pointed in the direction of the target for a minute or so, then eject it. I then treat it like a coiled rattlesnake... but... then I pick it up, chamber it, and it has always gone "BANG" the second time. It's a wonder I grew up and another that I still have my eyesight. Since age 8 I have always liked blowing things up and making things go bang. At 8, I looked at the remains of crackerballs and deduced the small rocks as the ignition source of the powder within. I got a pinch of small rocks, put them with "dud" firecracker powder in a twisted piece of grocery bag. I set those off with a length of 3/4" water pipe which must have protected my eyes, but rattled my ears and numbed my hands.! Recycling!!
When I was about 11, I got a chemistry set. I quickly ran out of saltpeter, sulfur, and powdered charcoal... and iron filings and the means to make sufuric acid to produce hydrogen... wheee! Then there were the empty CO2 cartridges, home-made gunpowder, and some kind of fuse (even some model rocket motor igniters) that I tried to power a wheeled "rocket car". Turns out it was a better grenade than rocket!!! I'm a little more cautious these days, even though I'm a "young 63".
I got refills for most of that at the local drugstore! Can you imagine that today??
Wynn

PS: Most people didn't live through the "good old days" when a young boy could ride a bicycle with a .22 rifle slung on his back to go hunting or target shooting and just have people smile and wave... instead of calling out the SWAT!!