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View Full Version : Damage to live ammo from too many load cycles!


Wyoredman
February 17, 2012, 05:16 PM
I read on the Boloreport http://boloreport.com/officer-safety-ammunition-cycling-and-failure-to-fire where an officer had a FTF during a leathal force situation.

When the ammo manufacture studdied the round in question, they concluded that the primer material had been knocked loose from the primer because of repeated loading into the officers' service pistol.

I had never thought about this, but I bet you I am now going to be rotating ammo in my CCW pistol!

Just wanted to let you all know about this.

Cycrops
February 17, 2012, 07:52 PM
I have been wondering about this and meant to search for (or start) a thread.

I keep my gun loaded with JHP ammo with a round in the chamber.

Any time I go to the range or do dry fire practice, I remove the magazine with JHP ammo, eject the chambered round, and add it back to the magazine. Once I'm done practicing, the JHP goes back in the gun.

How many times can you do this before the ammo is at risk? Emptying the magazine and reloading it in a different order with the same rounds doesn't seem like a much better solution. HD ammo is so much more expensive than FMJ that I'd prefer not to shoot it very often.

Sparks1957
February 17, 2012, 08:14 PM
I always shoot the SD rounds in my mag, then reload it afterward. First, it's a function check on the magazine, and second, it prevents any setback or other ammo damage from repeated loading/unloading.

So, you shoot a few rounds of more expensive ammo once in awhile, no big deal

Cycrops
February 17, 2012, 08:35 PM
I always shoot the SD rounds in my mag, then reload it afterward. First, it's a function check on the magazine, and second, it prevents any setback or other ammo damage from repeated loading/unloading.

So, you shoot a few rounds of more expensive ammo once in awhile, no big deal

I've got 17-round magazines. I try to get to the range every other week. The JHP ammo I use costs close to $1 per round, compared to $0.20 per round for the FMJ I use at the range. I'd rather not spend an extra $30 per month to keep fresh JHP ammo in my gun.

The cop in the story had rechambered and extracted the same round 100X, which I can understand is too much. My question is, how many times can you rechamber before you risk damage to the round?

9mm
February 18, 2012, 02:05 AM
we discovered that since he has small children at home, he unloads his duty weapon daily
This caused an internal failure of the primer, not discernible by external inspection. 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
http://boloreport.com/officer-safety-ammunition-cycling-and-failure-to-fire#

I had no clue those could happen, THANK YOU!!!!!

ANother reason to carry a back up.

JohnKSa
February 18, 2012, 02:29 AM
The cop in the story had rechambered and extracted the same round 100X, which I can understand is too much. My question is, how many times can you rechamber before you risk damage to the round? It depends on the ammunition, and to some extent, on the gun it's being used in. Some guns drive the round hard into the feedramp while in other designs the round feeds almost direcly into the chamber. As far as ammunition goes, I've had some factory ammunition that would set back noticeably from only one chambering.

If you're talking about premium self-defense ammunition, under 5x is probably safe.

If you want to push the limits, it would probably be best to contact the ammunition manufacturer directly, however, if you have some fresh ammunition from the same box, you can check your old rounds to see if they're setting back. Set two new rounds on a flat surface with an old round between them and put a straightedge across the top of the two new rounds. If there's a noticeable and significant gap between the straightedge and the top of the old round then the old round is garbage.

Different loadings and calibers exhibit different sensitivities to setback, but in a particularly sensitive loading, like the 180gr .40S&W, discharge pressures can double from only a tenth of an inch of setback. That's enough to take most any gun apart in abruptly impressive fashion.

Unless your circumstances dictate that you load and reload frequently, a better solution is to avoid the process. For example, with only a very few exceptions, a modern handgun in a good quality holster that covers the trigger can be safely stored that way as long as it is kept out of unauthorized hands.

Hook686
February 18, 2012, 02:34 AM
I avaoid this problem by using a revolver. In the ever pistol Vs revolver discissions I never heard this problem surface. Makes sense to me.

briandg
February 18, 2012, 03:33 AM
a person could easily and completely avoid this problem by slowly easing the round into the chamber instead of letting the slide slam it in.

the police in our area were encouraged to never chamber a round twice. pull the mag, eject that round, and drop the round from the chamber into a practice box. This was before the days of $1 a round hollow points.

I honestly don't see that this is a huge risk. Primer compounds are plasticized into a pellet, then covered with paper. it's not like they're a loose powder that will sift out. They are designed and manufactured to be durable and shock resistant. Of course, slamming them around in a handgun over and over could damage the pellet, but I'm thinking that it must still be a really rare occurrence.

JohnKSa
February 18, 2012, 03:39 AM
a person could easily and completely avoid this problem by slowly easing the round into the chamber instead of letting the slide slam it in.That's never a recommended approach for chambering a round because it can result in the slide not going fully into battery. If it that happens, the gun can misfire.

briandg
February 18, 2012, 03:44 AM
Are you talking about dropping the round in the chamber, or letting the slide strip the round?

I can see that objection if a round was fed into the chamber, but fed from the magazine, that seems pretty far fetched.

In any case, once again, the solution would be to eyeball the thing and make sure that it was fully into battery. I've never had a handgun that you couldn't visually confirm that.

Sparks1957
February 18, 2012, 04:31 AM
I've got 17-round magazines. I try to get to the range every other week. The JHP ammo I use costs close to $1 per round, compared to $0.20 per round for the FMJ I use at the range. I'd rather not spend an extra $30 per month to keep fresh JHP ammo in my gun.

OK, I can see your point. So, set your loaded SD mag aside and practice with your cheaper rounds... It's then the first round that you need to be concerned about, the one that is repeated stripped from the mag and chambered... so fire that one once in awhile, should be the end of your worries

JohnKSa
February 18, 2012, 06:37 AM
I'm talking about "slowly easing the round into the chamber" instead of feeding it into the chamber as intended by letting the slide slam it home. Whether it's fed from the magazine or direct chamber loaded*, the proper method to insure the gun goes fully into battery is to pull the slide all the way back and let it go forward with full force.

*Assuming the gun is designed to tolerate direct chamber loading without damage to the extractor.In any case, once again, the solution would be to eyeball the thing and make sure that it was fully into battery. I've never had a handgun that you couldn't visually confirm that.Sometimes it's not as easily determined as one might think. I would say it's reasonably likely one could verify that the gun is fully in battery, but we're sort of losing track of the point of the thread. The point of all this is to make things safer and to reduce the chances of malfunctions. It doesn't make sense to do that by advocating an unorthodox loading technique known to increase the chance of misfires followed up with a visual inspection that might or might not determine if the loading technique worked properly.

The bottom line is that autopistol ammunition isn't meant to be chambered an unreasonable number of times. That's a basic limitation of autopistols and autopistol ammunition and nothing's going to change it. The solution isn't to try to load the pistol using a non-recommended technique and then hope you can detect any problems caused by that approach, it's to treat the ammunition as it is intended to be treated.

Chamber it a few times and then discard it or use it at the range. I'd say that it makes sense to combine that approach with a careful re-evaluation of whether it's really necessary to load/reload one's pistol as frequently as some folks seem to do it.

Even if one isn't constantly rechambering ammunition, there are still other sound reasons why self-defense ammunition should be cycled through to the range on some sort of a reasonable schedule.

pjp74
February 18, 2012, 07:51 AM
I know its not as often as I should, but when it's time to move the clocks forwards or backwards twice a year, all carry guns/ammunition get taken to range and discharged and mags filled back up with fresh ammo. Yes, my SR9 has 17 round mags as well, but $15-$25 vs. at the moment of truth get "click" instead of "bang", I'll spend the extra $$. I have had setback problems with .45ACP in the past with certain 1911s that needed a good polishing to the feed ramp.

Cycrops
February 18, 2012, 08:23 AM
OK, I can see your point. So, set your loaded SD mag aside and practice with your cheaper rounds... It's then the first round that you need to be concerned about, the one that is repeated stripped from the mag and chambered... so fire that one once in awhile, should be the end of your worries

Good idea, thanks!

Spats McGee
February 18, 2012, 10:43 AM
The difficulty I had was figuring out how to remember which rounds I had chambered, and which ones were "fresh." Someone posted an idea here recently that I've decided to shamelessly steal. Sadly, I don't recall who originally posted this idea, but here it is:
1) After a round has been chambered and unchambered, take a permanent marker, and make a mark on the bullet.
2) Every time you take that unfired round out of the chamber, make another mark. (The original poster recommended putting 1 mark across the top of the bullet. Then the second mark would go across the first one, forming an X. This obviously wouldn't work for hollowpoints.)
3) When the number of marks hits the number of times you're comfortable chambering the round (or one less), move that round to the bottom of the magazine, and chamber the next round.
4) When all of the rounds in the magazine are marked up so that you don't want to chamber them any more, it's time to burn them off at the range.

I realize that the above doesn't answer the question of "how many times can you safely chamber a round," but it does help keep track of how many times I have chambered a round.

Sarge
February 18, 2012, 11:20 AM
Some folks choose to leave the chamber empty on auto stored around the house, etc. I won't argue that point with them; it is their choice. I stripped duty guns of their chamber load daily when we had small kids in the house.

During that time I noticed a number of rounds, of various calibers, showing early signs of set-back. If it was minor, I tossed them in the 'oddball ammo' can and simply shot them up later. None of them ever failed to fire. If it was pronounced, I threw them in the pond.

When the mag got down a round or two I simply topped it off with new ammo.

I often squeeze the slide lightly, with the thumb and index finger of my weak hand, when chambering a round from the mag. Guess I got started doing this after working on 1911's for decades... it gives me a read on how slick the gun is feeding and I've never had the slide hang out-of-battery.

I can't imagine not knowing if my slide was in battery.

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.

IF the primer got hit a good lick, I wonder how you tell that the compound got knocked out of the primer cup by cycling it? Oh well...

wayneinFL
February 18, 2012, 12:34 PM
I've always rotated ammo in the mags every few times they're used, just because of bullet setback. Then I fire them off at the range occasionally. Never thought about the primer being damaged. IMO, bullet setback is more serious an issue than a bad primer, because of overpressure. A ruptured case (or chamber:eek:) is going to be harder to clear than a round that simply doesn't fire.

If I ever got to the point I had issues with my carry ammunition when I fire them at the range, I would do rotate it more often.

If you're really concerned about it, carry a revolver. :p

federali
February 18, 2012, 06:05 PM
Too many trips through the action and the extractor tends to chew up the rim which could result in erratic extraction. I too clear my expensive street loads at the range and substitute reloads. However, I do inspect them and any that are showing some wear get shot off.

briandg
February 18, 2012, 06:36 PM
The bottom line is that autopistol ammunition isn't meant to be chambered an unreasonable number of times. That's a basic limitation of autopistols and autopistol ammunition and nothing's going to change it. The solution isn't to try to load the pistol using a non-recommended technique and then hope you can detect any problems caused by that approach, it's to treat the ammunition as it is intended to be treated.

Chamber it a few times and then discard it or use it at the range. I'd say that it makes sense to combine that approach with a careful re-evaluation of whether it's really necessary to load/reload one's pistol as frequently as some folks seem to do it.

Even if one isn't constantly rechambering ammunition, there are still other sound reasons why self-defense ammunition should be cycled through to the range on some sort of a reasonable schedule.


Agreed.

Freakdaddy
February 19, 2012, 08:41 AM
I keep all of my carry guns loaded with one in the chamber at all times. Which ever one I decide to take to the range, I remove the mag of HST's, insert a mag of FMJ's and the one HST in the chamber gets fired off first. After cleaning, I chamber another HST from said mag then top it off with one from my reserve box. By doing it this way, I have no concerns about bullet setback as none of mine are getting rechambered. Works for me.

Skadoosh
February 19, 2012, 09:18 AM
Good thing I carry a revolver!

Some folks choose to leave the chamber empty on auto stored around the house, etc.

As a former firefighter, SOP at my department was not to enter a house that was on fire if there was a suspicion that there were loaded firearms inside. I download all weapons when storing them.

Sarge
February 19, 2012, 09:48 AM
As a former firefighter, SOP at my department was not to enter a house that was on fire if there was a suspicion that there were loaded firearms inside. I download all weapons when storing them.

Hell they would ALL burn to the ground around here. Everybody keeps them and everybody knows it.

Vermonter
February 19, 2012, 11:58 AM
I can see how rechambering can be bad for a round. I typically do not re chamber the same round multiple times. My question however is what about rounds being removed and then re loaded into mags.

My typical range trip starts with me dropping the mag of carry ammo. My spare mags are also loaded with carry ammo and kept either on me or in the truck. I fire the chambered round and replace that one but I typically sit my hat on the table and unload all my carry ammo from the mags into the hat.

I then use those mags for range work with whatever I choose to pratcice with and reload them at the end of the session. Any info on rounds damaged because they were placed into a mag and then removed?

Thanks, Vermonter

Sarge
February 19, 2012, 12:26 PM
If they look anything like this-or worse-toss them.

http://i186.photobucket.com/albums/x187/SargeMO/45_setback.jpg

AH.74
February 19, 2012, 12:31 PM
Vermonter- you might want to inspect them but I can't say I've seen mention of damage from loading and unloading from mags only.

I know that people re-chamber sometimes without seeing any appreciable setback. But after finding this I stopped doing it more than the initial time. I was quite surprised. It is a Speer GD standard pressure 124g 9mm that was chambered only once. I had previously re-chambered rounds 2-3 times without seeing anything like it.

http://i226.photobucket.com/albums/dd6/ah74/setback.jpg

Vermonter
February 19, 2012, 03:10 PM
Ah74 wow that pic says alot. I will be inspecting every round looking for this now.

Skadoosh
February 19, 2012, 04:37 PM
So...is that enough setback to be dangerous?

JohnKSa
February 19, 2012, 07:15 PM
It could be dangerous in certain loadings of some calibers. Typically it's more of an issue in heavy bullet loadings of calibers without a lot of case capacity. .40S&W with 180gr bullets is probably the classic example. As I mentioned earlier, in that loading, a tenth of an inch of setback can double the discharge pressure.

Merad
February 19, 2012, 08:07 PM
The last SD ammo I bought (Federal 9mm 147gr and .380 92 gr HP's) both have sort of a crimp in the case at the bottom of the bullet, presumably to help prevent setback.

Personally, I just check them before rechambering...

Nnobby45
February 19, 2012, 08:24 PM
When a gun is well broken in, the round will chamber easy enough when slow fed into the chamber. Riding the slide part way home before letting it go is a better description. This is a technique I've always used to keep from dinging up the bullet nose, or risk setting the bullet back in the case. "Administrative" loading only! Even so, I still like to rotate that top round to the bottom after a couple loadings.

Never to be used for SD practice where the slide has to be released with full force to insure positive chambering.

Steviewonder1
February 19, 2012, 10:49 PM
I always drop the "Social Mag" from the gun going into the range and leaving the gun in the Gun Bag regardless of the rules. It is safe and when getting to my range station, remove the gun from the gun bag and load the Range Ammo mag into it. No one complains and cannot tell the difference. When exiting the range into my vehicle, I load a fresh mag rack the slide and top off the mag with one bullitt in the parking lot. This is done with the drivers side window open and gun pointing up. Never had a problem and NO set back issues with my "Social Ammo" YMMV.