The Firing Line Forums - View Single Post - How many times can you chamber a round safely?

Dfariswheel · January 4, 2020, 08:41 PM

The real danger of set back is not so much higher pressures, although that IS a problem.
The problem came to be known as "Second round stoppage" and it caused some stoppages in actual police shootouts, some of which were caught on squad car cameras.
The cop could be seen firing a first shot then his pistol would jam.

In the early days of the police move to the auto pistol they had a rash of situations where the gun would fire the first round, then fail to properly feed the second round, causing a jam.

This was traced to the police pistol inspection process.
People would remove the mag and clear the chamber for inspection, then insert the mag, chamber the round, then put the first round back in the magazine.
This meant that the same two rounds were being chambered over and over, pushing the bullets back into the case.
The stoppages were caused by rounds that had too short an overall length and would miss-feed.

To fix the problem police were trained to not chamber the same rounds more then a couple of times, and ammo makers began making ammo for police use that were made to allow more chamberings without excessive set back.
Most police ammo makers warrant the ammo for 3 to 4 trips into the chamber before it should be fired in practice or discarded.

To help eliminate problems, some people take a factory fresh round out of a new box of ammo and store it.
Then, they use the factory fresh round as a "gauge" to check for bullet set back in the ammo that's in use.
When you see the bullets beginning to move into the case, stop using it and shoot it in practice.

January 4, 2020, 08:41 PM	#18
Dfariswheel Senior Member Join Date: May 4, 2001 Posts: 7,478	The real danger of set back is not so much higher pressures, although that IS a problem. The problem came to be known as "Second round stoppage" and it caused some stoppages in actual police shootouts, some of which were caught on squad car cameras. The cop could be seen firing a first shot then his pistol would jam. In the early days of the police move to the auto pistol they had a rash of situations where the gun would fire the first round, then fail to properly feed the second round, causing a jam. This was traced to the police pistol inspection process. People would remove the mag and clear the chamber for inspection, then insert the mag, chamber the round, then put the first round back in the magazine. This meant that the same two rounds were being chambered over and over, pushing the bullets back into the case. The stoppages were caused by rounds that had too short an overall length and would miss-feed. To fix the problem police were trained to not chamber the same rounds more then a couple of times, and ammo makers began making ammo for police use that were made to allow more chamberings without excessive set back. Most police ammo makers warrant the ammo for 3 to 4 trips into the chamber before it should be fired in practice or discarded. To help eliminate problems, some people take a factory fresh round out of a new box of ammo and store it. Then, they use the factory fresh round as a "gauge" to check for bullet set back in the ammo that's in use. When you see the bullets beginning to move into the case, stop using it and shoot it in practice.