The unexplained Ka-booooooom - explained?
Author |
Message |
plblark
|
Post subject: Posted: Fri Apr 06, 2007 10:33 am |
|
Longtime Regular |
|
Joined: Thu Mar 16, 2006 10:41 am Posts: 4468
|
ChillyW wrote: joelr wrote: Interesting.
Orthogonally, we ran into the opposite sort of problem last Sunday, when I was doing some quals down at Burnsville. My 642 repeatedly jammed with Blazer .38s. Upon examination, it became clear that the crimp wasn't just inadequate, but missing -- bullets got pulled enough to prevent the cylinder from rotating. I've had the exact same problem. Same gun, same ammo. No more Blazer ammo for me. Does Winchester do white box .38?
yep
|
|
|
|
|
DeanC
|
Post subject: Posted: Fri Apr 06, 2007 4:59 pm |
|
Longtime Regular |
|
Joined: Thu Mar 09, 2006 9:54 am Posts: 5270 Location: Minneapolis
|
cobb wrote: A match cartridge gauge would check if a cartridge is too long, Actually, no. It would check if the case was bulged or if you had a crappy crimp. The ones I use have nothing to do with OAL. They're cheap, less than $15.
_________________ I am defending myself... in favor of that!
|
|
|
|
|
jdege
|
Post subject: Posted: Fri Apr 06, 2007 5:46 pm |
|
Longtime Regular |
|
Joined: Thu Aug 25, 2005 7:23 pm Posts: 1419 Location: SE MPLS
|
Pred wrote: So what's a guy to do with the previously loaded round?
Shoot it.
The problem is repeated rechambering, not rechambering once or twice. A lot of folks carry expensive HPs, and shoot cheap FMJs. And so every time the shoot, they eject an HP, load up with FMJs, shoot, then rechamber the ejected HP.
The fix is to shoot out your carry magazine, every once in a while.
|
|
|
|
|
mostlylawabidingcitizen
|
Post subject: Posted: Fri Apr 06, 2007 8:23 pm |
|
Joined: Fri Aug 26, 2005 7:54 am Posts: 1242
|
There was a time when every night when I put my Sig 229 (40 cal) on the shelf at night, I would remove the chambered round insert it back into the mag and then the next morning I would re-chamber the round. Then I noticed that the round started getting shorter and had a indented ring around the casing (hydro-shocks). I no longer clear the gun every night, now I'm going to have to go through my mags and throw out any short collared rounds.
I didn't realize the issue could be so troublesome though.
Mostly-
|
|
|
|
|
cobb
|
Post subject: Posted: Fri Apr 06, 2007 9:39 pm |
|
1911 tainted |
|
Joined: Sun Aug 07, 2005 2:47 pm Posts: 3045
|
DeanC wrote: cobb wrote: A match cartridge gauge would check if a cartridge is too long, Actually, no. It would check if the case was bulged or if you had a crappy crimp. The ones I use have nothing to do with OAL. They're cheap, less than $15.
I miss spoke, it would check if it will chamber. And as you point out, in most cases when a round won't chamber it is something bad in the crimp area.
So they won't check if they are too long overal, or if the bullet has been pushed into the case, causing increased pressure.
|
|
|
|
|
JFettig
|
Post subject: Posted: Tue May 08, 2007 8:18 am |
|
Senior Member |
|
Joined: Thu May 03, 2007 12:16 pm Posts: 115 Location: Willmar and Fargo
|
I'm a little late in this topic but...
I've not seen this in my own carry ammo thats been chambered multiple times. But ever since I've read about this a while back I chamber the first round very carefully, slowly until it enters the chamber then let it go so that the feed ramp doesn't push it back. I only do this with my carry ammo.
I recently shot off my hydra-shock ammo that I had in mags to cycle new stuff in. I have no idea how old this stuff is, I didn't even know what brand it was until I got new hydra-shocks.
Jon
|
|
|
|
|
hypertech
|
Post subject: Posted: Tue May 08, 2007 9:11 am |
|
Joined: Sun Nov 26, 2006 10:40 pm Posts: 363
|
joelr wrote: Interesting.
Orthogonally, we ran into the opposite sort of problem last Sunday, when I was doing some quals down at Burnsville. My 642 repeatedly jammed with Blazer .38s. Upon examination, it became clear that the crimp wasn't just inadequate, but missing -- bullets got pulled enough to prevent the cylinder from rotating.
I had the same problem with Sellior & Belloit lead nose. They replaced it with FMJ. I don't remember if I have shot it yet and if I had the same problem with that box or not.
I didn't look at the crimp, but the bullets were most certainly shaking loose and coming out.
|
|
|
|
|
sheepdog
|
Post subject: Posted: Tue May 08, 2007 12:20 pm |
|
Senior Member |
|
Joined: Tue Apr 24, 2007 8:25 pm Posts: 367 Location: Forest Lake, MN
|
I know for a fact that I have re-chambered at least of few of the rounds in the magazine currently in my XD. I don't like to keep a round chambered unless the gun is on my hip, so (like mostlyabiding used to do), I pop the chambered round out prior to storage.
I have a pretty decent digital caliper. Does anybody know the nominal OAL and tolerance for a Speer Gold Dot in .40S&W? Also, what type of deviation from the nominal length would be deemed unacceptable? If I see a shift of .001" from nominal, would I need to be concerned?
I like JFettig's idea of slowly chambering the round until it clears the feed ramp. Is the pressure applied by the feed ramp during chambering the only thing that would cause this type of situation?
|
|
|
|
|
plblark
|
Post subject: Posted: Tue May 08, 2007 3:11 pm |
|
Longtime Regular |
|
Joined: Thu Mar 16, 2006 10:41 am Posts: 4468
|
I don't have experience with the Gold Dots in my .40S&W yet but I have a CorBon .45ACP that has been seriously set back which reminds me to be VERY careful about repeated chamberings.
Perhaps a mag with your chamber rounds would do the trick?
It goes like this. buy 2 boxes of gold dots. Load 3 mags. 1 is for in the gun, 1 is for spare, and one is used only to first chamber a round.
In the morning, you drop the carry mag from the gun which has an empty chamber. you load the "chambering" mag and chamber a round. you drop the "chambering" mag and put it back in the safe. you insert your carry mag. Put the spare Mag in your pocket.
End of day, drop carry mag, eject chambered round. insert carry mag (without chambering). put ejected shell in separate container to be used at the range.
This way you put a box of carry ammo through your gun a month without chambering any round more than once. When you buy new ammo, your carry mag becomes the chambering mag, the spare goes to carry and you load up a new spare.
Kinda a built in rotation. Complex though.
If you wanted to chamber each round twice, just reload the chambering mag one time once it's empty but after the second chambering, put it in the range bag.
|
|
|
|
|
mnglocker
|
Post subject: Posted: Tue May 08, 2007 6:07 pm |
|
Longtime Regular |
|
Joined: Wed Jul 19, 2006 12:04 pm Posts: 1682 Location: Wright County
|
JFettig wrote: I'm a little late in this topic but...
I've not seen this in my own carry ammo thats been chambered multiple times. But ever since I've read about this a while back I chamber the first round very carefully, slowly until it enters the chamber then let it go so that the feed ramp doesn't push it back. I only do this with my carry ammo.
Ditto, not a proplem with mine yet either and I carry .40s&w in a Glock.
|
|
|
|
|
HOPPES9
|
Post subject: Posted: Fri May 18, 2007 12:55 am |
|
Joined: Thu Aug 10, 2006 5:53 pm Posts: 235
|
If anyone has a Beretta model 92FS, the owners manual states you should not rechamber the same round all the time. I don't remember the frequency they suggest not rechambering the round.
|
|
|
|
|
KonaSeven
|
Post subject: Posted: Wed May 23, 2007 9:22 pm |
|
Longtime Regular |
|
Joined: Thu Aug 31, 2006 12:17 pm Posts: 908 Location: Meeker Co., MN
|
Interesting discussion from a company addressing the setback problem. Fascinating that they are currently only considering ball ammo at this time. For functionality in 1911's it would appear.
.45 ACP Special Ball Ammunition Article
Quote: Ammunition with non-cannelured cartridge cases can allow bullets to be pushed back during the feed cycle, either all at once, or in small increments during multiple manual feedings. This can cause stoppages, and other problems. In this photo the cartridge on the left of each pair is new from the box. The right cartridge was manually cycled through the pistol 10 times. Note how much bullet set back has occurred. Easily enough to cause a pistol stoppage.
_________________ 1 of 55153
"The attitude of people associating guns with nothing but crime, that is what has to be changed. I grew up at a time when people were not afraid of people with firearms." —Supreme Court Justice Antonin Scalia
Sierra Trading - Firearms Sales, Service and Training
|
|
|
|
|
Pinnacle
|
Post subject: Posted: Thu May 24, 2007 7:25 am |
|
Designated waste of protoplasm |
|
Joined: Fri Feb 24, 2006 4:41 pm Posts: 1807 Location: Western Burbs of MPLS
|
here is a little trick
CHAMBER THE ROUND - CLOSE THE GUN ON THE ROUND (yeah I know - people say not to do this as it is bad for the extractor - my experience says different.)
Here is another trick - take carry ammunition and re-crimp it with a LEE Factory Carbide Crimp Die.
It forms a mechanical lock so that the bullet WILL not and CANNOT sink into the case.
|
|
|
|
|
Selurcspi
|
Post subject: Posted: Thu May 24, 2007 11:08 am |
|
Longtime Regular |
|
Joined: Fri Feb 24, 2006 1:02 pm Posts: 1569 Location: The Mild, Mild, West, Burbs
|
_________________ NRA Certified Instructor MADFI Certified Instructor MN DNR Certified Instructor UT BCI Certified Conceal/Carry Instructor
"If you expect the police to always be able to protect you, why are the ones who show up at crimes called 'detectives' instead of 'defenders'? Detectives try to find a criminal after they've committed a crime."
|
|
|
|
|
This is a static archive the Twin Cities Carry forum, maintained as a public service by the current forum of record, The Minnesota Carry Forum.
All times are UTC - 6 hours
Users browsing this forum: No registered users and 6 guests |
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum
|