I read recently (it seems like, in a few different places) that chambering the same round repeatedly is dangerous because it packs the bullet farther into the casing further increasing the pressure. That sounds like bull to me. Maybe I just dont understand the interworkings of a semi auto handgun but it doesnt seem like anything exerts pressure on the bullet itself. At least not enough to pack it into the casing.
Get yourself either a micrometer, or a set of dial vernier calipers, and measure the overall length of a new round. Put the round into the mag, and whip the slide to drive the round into battery. Eject the round, and measure it again. Repeat, and keep doing this. You'll definitely notice the round getting shorter.
As the round gets shorter, and the bullet keeps getting driven deeper into the case, the combustion chamber becomes smaller inside the case. When fired, the combustion pressures will be far higher than they normally would. Could be dangerous, maybe not. Your gun, and your hand.
Most folks won't take the chance, and will either toss the short rounds, or pull the bullet back out with a bullet puller and then reseat it in a reloading press.
This taken from Speer Reloading no 11 on 9mm. "If the bullet is easily moved deeper into the case, malfunctions may occur. But more important, loads that produced 28,000 cup went to 62000 cup when bullets were purposely seated .030" deeper! Thus, it is of the utmost importance that bullets do not become deeper seated in the feeding cycle. A case cannelure below the bullet base will preclude this occurrence."
Any gun not designed to handle that kind of pressure will catastrophically fail; yes, even steel.
I agree 100%. Maybe it's just because of the pure volume of Glocks out there, but I have yet to see visual evidence of another polymer pistol that has suffered a failure like we've seen the Glocks suffer. It's bound to come up though, now that hundreds of police agencies have dropped Glocks and picked up S&W M&P's and Springfield XD's.
If you carry, say, a .45, and routinely load and unload it, take all the rounds out of the mag and line them up. Then put a ruler across the top and see if they're all the same height. Might surprise you. And .030 isn't very much.
__________________
I child-proofed my house, but they still keep getting in!
I agree 100%. Maybe it's just because of the pure volume of Glocks out there, but I have yet to see visual evidence of another polymer pistol that has suffered a failure like we've seen the Glocks suffer. It's bound to come up though, now that hundreds of police agencies have dropped Glocks and picked up S&W M&P's and Springfield XD's.
I'd say I'd like to see that to show that it's not just the GLOCKs that do that in a kB!, but at the same time, I'd rather it not ever happen to anyone ever again, especially law enforcement and especially if they're in the line of duty.
__________________
B.S. Chemistry UofWA '09
CETME Owners - Founder
AK-47 - Member
The Mosin Men - Member
KF7GEA
I have 20 powerball shots and I believe they are crimped. I suppose I don't have to worry about that then.
A cannellure is that indented circle around the bullet. Put a crimp in that and it's not going to move or very little. Many handgun bullets that I've seen don't have them so although yours are crimped they are still likely to move if they don't have a cannullure. The danger is real about the loading and unloading!
Well I was thinking about this thread as I found my wife's box of ammo from our last outing to the range. She had one round that DID get chambered but she decided to stop for the day. Here it is beside a round that had not been chambered. Notice the difference in length. Im guessing it has the crimping that you were talking about too.
Well I was thinking about this thread as I found my wife's box of ammo from our last outing to the range. She had one round that DID get chambered but she decided to stop for the day. Here it is beside a round that had not been chambered. Notice the difference in length. I'm guessing it has the crimping that you were talking about too.
Ander254, I also noticed that the shorter bullet on the left appears to have a plier or other mark on the brass as well? What might have caused that? Something in the gun you might want to inspect maybe?
__________________ "My next door neighbors two dogs have created more shovel ready jobs then Obama has." - Gary Johnson
Last edited by GlockMeister; 04-11-2008 at 06:33 PM.
Ander254, I also noticed that the shorter bullet on the left appears to have a plier or other mark on the brass as well? What might have caused that? Something in the gun you might want to inspect maybe?
That mark on the case is a canilure on the case to stop the bullet from backsetting to a dangerous point,the only way to really stop bullet backset. sam.
recycle the same bullet through the chamber repeatedly. I do agree with the othe posters but must admit this is just not something I would do anyway as it is better to practice and hunt then load fresh ammo into a properly cleaned/lubricated firearm.
Location: a secret lab on the shores of lake titicaca
Posts: 23,062
Quote:
Originally Posted by samuel
That mark on the case is a canilure on the case to stop the bullet from backsetting to a dangerous point,the only way to really stop bullet backset. sam.
so THATS what those are for!
thanks sam.
i accidentally learned something again!
__________________ "I don't practice what I preach because I'm not the kind of person I'm preaching to."
Ander254, I also noticed that the shorter bullet on the left appears to have a plier or other mark on the brass as well? What might have caused that? Something in the gun you might want to inspect maybe?
Not sure what caused the mark but it was a range gun. Its only on one side of the bullet so I might have done that loading it on the mag.
