Bullet Setback

[Bigguy]

This is an embarrassing post to make. I'm confessing my ignorance and the ignorant actions that almost got me into trouble. Non-the-less, I don't want to let my pride stop me from posting on a topic that might help somebody else. While I'm sure most of the member who routinely post here are already aware of this, there may be other folks, who like me lurk more than post, and might be unaware of this potential danger.
I'll copy my original post below, but there is a lot of good information in the responses from other members. I'm sure some of the knowledgable people here will also contribute valuable advice.


Bullet setback thread on Texas CHL forum
I want to thank the CHL and it's members. Specifically those responding to the thread "Carrying With One Loaded In Chamber (Question?)
Somebody asked about leaving a round in the chamber. They had heard that it somehow damaged the cartridge.
I had developed the routine of ejecting the magazine every night, racking the slide to eject the chambered cartridge. I'd then hold the muzzle to a lamp so that light shines down the barrel, demonstrating no obstruction. I'd do a quick visual, then reinsert the magazine and release the slide lock, confirming the mechanisms fed properly. I'd then eject the magazine again and reload the cartridge, previously in the chamber, back into the magazine. Basically I was recycling two cartridges back and forth between the chamber and the top of the magazine. After reading that thread I decided to check my gun. Here is what I found:

The cartridge on the right is one of the two I'd been rotating with my nightly routine. The one on the left is fresh from the box.
You guys may have saved me from injury. I spend quite a bit of time on this, and the Pistol Forum in order to learn from knowledgeable people talking about guns. While it's embarrassing to write about my ignorance and ignorant actions, I decided to swallow my pride and fess up in order to thank you guys and let you know that there is real good in the exchanges between you on this board.

[Dave J]

Consider obtaining some sort of lockbox for your carry gun. If you remove the gun from your person, simply leave it loaded, and lock it up.

I'd suggest using a dedicated container for this, rather than mixing loaded and unloaded guns together in a larger safe.

If you must download, the round from the chamber goes in the training pile. If I am short on carry ammo for some reason, I'll mark the cartridge with a Sharpie, and chamber it no more than one additional time.

And thanks for posting that picture! I'm sure it will help drive the message home. (If you don't mind, I'd like to copy that picture, and add it to my teaching slides)

[Bigguy]

(If you don't mind, I'd like to copy that picture, and add it to my teaching slides)

I don't mind at all. I'm grateful for the opportunity of assist in a teaching opportunity.
I don't need photo credit for it though.

[Jay585]

Thanks for posting this.

I'm curious - what happens if one were to fire the reduced-OAL round?

[EricP]

Thanks for posting this.

I'm curious - what happens if one were to fire the reduced-OAL round?

Chamber pressure skyrockets. In my one experience, it blew the magazine out of the gun, felt like someone hit me in the hands with a bat, and scared the living kittens out of me.

Mine wasn't from rechambering the same round, but what I suspect was missing the crimping stage of assembly.

[Chuck Haggard]

Someone thought that leaving a round in the chamber damages the cartridge?

Seriously? I'm not trying to be an ass, I've never heard that one before.


Clearing the gun daily is a really bad idea, FAR better to use a lock box.


Also, you are carrying FMJ as carry ammo?



And yes, set back can more than double chamber pressure and blow up the gun. I have seen several LE advisories over the years ref blown up guns, mainly from agencies that insist on loading/unloading a lot, like the guys that guard the nuke plants.

Even if you do not get set back you can end up damaging the primer internally and have a dead round. I have seen a couple of LE advisories on this as well. I also know a guy who had a bad day in Iraq, tries to shoot a bad guy, M4 goes click, transition to Glock 19, G19 goes click. Fortunately he was squared away and got the guns running and finished the problem.

[Chuck Whitlock]

Someone thought that leaving a round in the chamber damages the cartridge?

Seriously? I'm not trying to be an ass, I've never heard that one before.


Clearing the gun daily is a really bad idea, FAR better to use a lock box.


Also, you are carrying FMJ as carry ammo?



And yes, set back can more than double chamber pressure and blow up the gun. I have seen several LE advisories over the years ref blown up guns, mainly from agencies that insist on loading/unloading a lot, like the guys that guard the nuke plants.

Even if you do not get set back you can end up damaging the primer internally and have a dead round. I have seen a couple of LE advisories on this as well. I also know a guy who had a bad day in Iraq, tries to shoot a bad guy, M4 goes click, transition to Glock 19, G19 goes click. Fortunately he was squared away and got the guns running and finished the problem.

Besides the LE advisories, the info is in the archived newsletters at rangemaser.com.

[littlejerry]

I have never fired a round with a bullet setback in the case as shown in the photo. I would not recommend doing so either.

However,
Luckygunner Labs posted this report where they set a .40 S&W as far back as possible in a case and fired it, multiple times, without any adverse effects on a Glock 22.
https://plus.google.com/+luckygunner/posts/CiVxdHvWjYS

[EMC]

I have never fired a round with a bullet setback in the case as shown in the photo. I would not recommend doing so either.

However,
Luckygunner Labs posted this report where they set a .40 S&W as far back as possible in a case and fired it, multiple times, without any adverse effects on a Glock 22.
https://plus.google.com/+luckygunner/posts/CiVxdHvWjYS

Gotta love Luckygunner labs, the mythbusters of the gun world.

[Bigguy]

Also, you are carrying FMJ as carry ammo?

Another reason to be embarrassed. I'll snag the first box of JHP I can find. I do have JHP Gold Dot for my .380 BUG.