What keeps a semi pistol from going full auto with a dirty / stuck firing pin

T

TXAZ

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If you never cleaned a semi handgun after a very large number of rounds, can the firing pin get stuck i the firing position, then basically run as a full auto / open bolt?
 
If the firing pin is extended forward of the breechface, it would probably prevent a round from feeding into the chamber.
That would/should be the case with controlled-round feed, like a 1911, but if the round fed via inertia, then it would already be in the chamber when the bolt closed on it, and . . . pew.
 
The vast majority have a spring loaded firing pin. So the pins natural state is retracted. You are more likely to see light primer strikes then runaway slamfire.

SKS rifles, however have a free floating, firing pin (for example) and if gunked up enough can stick out of the breach face and slam fire / full auto.

Chris
 
Depends on the pistol. Most might fire 2 rounds and jam. It takes a lot more than a stuck firing pin to cause FA fire.
"...slam fire/full auto...." Far more likely to be caused by the ammo than the rifle.
 
Do a search for "`1911Tuner" and get the whole story...he's a gunsmith of some repute. Or...buy Kuhnhausen's gunsmithing guide on the 1911. YMMv Rod
 
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Striker fired autos tend to have a system that catches the striker/firing pin as the slide comes back forward. That would "unstick" the firing pin in most cases, or maybe just stop the slide in the case where the firing pin can't be unstuck.

As RickB points out, if the firing pin is stuck forward in a "controlled feed" gun where the round slips up behind the extractor as it feeds, the round will probably jam during the feeding process and hang up the gun.

In a situation where nothing actually prevents everything from operating normally then a gun with a stuck firing pin has a good chance of setting off the round prematurely--before it fully chambers--resulting in a blown case and possible injury.

But yeah, in some guns, the gun might fire full auto until the mag is empty. If the gun has decent recoil and the malfunction is unexpected, there's a good chance of someone getting hurt or killed as a full-auto pistol can really jump around a surprising amount.
 
With a protruding , stuck firing pin I don't think the round ready to be stripped from the mag would allow the extractor claw to completely hook the rim of the cartridge. This seems to be a high probability of a abrupt jam. (Just tying to logically speculate the occurance).
 
TXAZ said:
If you never cleaned a semi handgun after a very large number of rounds, can the firing pin get stuck i the firing position, then basically run as a full auto / open bolt?
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Depends on the gun. I had a Makarov with a gunked up firing pin channel double once.

As RickB points out, if the firing pin is stuck forward in a "controlled feed" gun where the round slips up behind the extractor as it feeds, the round will probably jam during the feeding process and hang up the gun.
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Which the Makarov (perhaps uniquely) is not. The extractor jumps the rim. ThaIt's the way it's made.
 
No, the disconnector won't allow it to happen.
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How would that work?

Disconnectors typically disconnect the trigger linkage to prevent the hammer or striker from falling when the bolt/slide returns forward on the feed stroke while the trigger is still pulled. If the firing pin is stuck forward in the firing position, how can the disconnector prevent the gun from firing when the bolt/slide slams forward into a chambered round?
Which the Makarov (perhaps uniquely) is not. The extractor jumps the rim. ThaIt's the way it's made.
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If the gun is not a "controlled feed" gun, then it shouldn't jam if the firing pin is stuck forward. Then you have a couple of other possible scenarios I described in my previous post.
 
It can happen with many designs.
What prevents it is you. Regular cleaning and inspections.
What keeps it from being a disaster is you: every time I release a slide I tell myself “this can go off” and grab tight. Some days I tell myself a lot. It’s the 10,000th time when you think all is routine that stuff bites you.
 
Ditto, many can go auto from gunk. The Jennings 22 pistol comes to mind. They run away and either shoot empty or jam. Charter Arms made a 22 pistol called Explorer, off AR7 design they were known to run away. Another one was a 32 or 380 marketed by Iver Johnson in 80s, imported, can’t remember the name of it. I’m sure there is a bunch of other ones too.
 
TXAZ said:
If you never cleaned a semi handgun after a very large number of rounds, can the firing pin get stuck i the firing position, then basically run as a full auto / open bolt?
Click to expand...
Many, many years ago, one of the first handguns I owned was a second hand High Standard Model B (no external hammer). At some point the firing pin broke in half and the forward half would lodge forward. I found that by inserting a full magazine, and letting the slide slam forward it would go into full auto for a few rounds. Although a few rounds would fire automatically, it never emptied the magazine completely...sometimes two, sometimes three, sometimes as many as four.
 
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