A "Failure to Extract" occurs when the slide or bolt move backwards, but the empty cartridge case remains behind in the chamber. In this situation, a new live cartridge may sometimes be forced into the base of the old case and the slide stays open and the firearm becomes jammed. This is called a "double feed". When this happens, the firearm can be difficult to clear.
Failure to Extract. Click on image to enlarge.
In the above image, we see a failure to extract, which causes a second cartridge to "double feed" into the chamber and leave the slide opened. The magazine may get stuck and refuse to drop out of the weapon. This type of jam sometimes requires some tools to clear the problem.
There are a few reasons why this can happen:
- Dirt and corrosion: This is the #1 reason for failure to extract. Dirt or corrosion in the extractor claw or firing chamber can cause the empty cartridge to not be picked up correctly.
- Damaged extractor: A damaged or bent extraction claw may not pick up empty cartridges correctly. A weak extractor spring could also cause this malfunction to happen.
- Defective cartridge: Due to damage around the cartridge rim, the cartridge may slip off the extraction claw and remain behind in the chamber. Bulges in the cartridge could cause excess friction on the sides, which causes the cartridge to slip off the extraction claw.
A failure to extract will cause the weapon to not fire any more, until the problem is cleared. The cost of fixing this is usually not that much, as cleaning dirt is a standard procedure that should be carried out with any firearm. Damaged extraction claws and extractor springs can also be replaced fairly cheaply, as these parts are not that expensive for most firearms. Defective cartridges can be disposed off and cartridges of better quality can be purchased instead.
I've been reading this blog for a while now, and I just wanted to say thank you for creating and maintaining this wonderful resource.
ReplyDeleteAs a relatively young gun enthusiast, hand loader, and hobby-level gunsmith, the information you've gathered here has been invaluable for understanding concepts I've wrestled with for months like the long-recoil and roller-delayed methods of operation. Whenever a friend needs help with a gun-related concept I almost always wind up sending them here to see it explained better then I could.
In short; I feel like it wouldn't be right to get so much information and not comment on anything
Thank you very much for your kind words Bones. They mean a lot to me. It is always nice to hear back from my readers.
ReplyDeleteYes, excellent information here! Thanks for taking the time.
ReplyDeleteI'm having this problem with my new Ruger American Compact pistol. With the first 200 rounds I ever shot through it, I got two FTEs/double feeds using Herter FMJ 115g brass ammo (fairly cheap). The next 350 rounds I got three FTEs/double feeds and I used some Fiocci and Federal American Eagle FMJ 115g brass ammo along with the Herter ammo. The failures were with the Herter ammo. So, the next 200 rounds I used nothing but Fiocci and Federal American Eagle and I got one FTE/double feed on round number 197. Very disappointing. By the way I cleaned the gun before I shot it for the first time and I cleaned it after every time I shot it. I want this to be a defensive carry gun but not sure if a 1% or even 1/2% failure rate is acceptable.
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