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Old January 14, 2018, 07:29 PM   #1
Kvon2
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1911 Thumb Safety Question

Hi all, just had this discussion earlier with a friend and neither of us were confident in the answer. It looks like there's a similar conversation going on currently but I have a pretty specific question.

Does the thumb safety(or the grip safety) block the firing pin when active? In other words, hypothetically, if there was a failure and the hammer dropped but the thumb safety was on(I understand this is HIGHLY unlikely), would the safety prevent the hammer from moving the firing pin?
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Old January 14, 2018, 07:34 PM   #2
BBarn
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Niether the thumb safety nor the grip safety blocks the firing pin on the original or
Series 80.
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Old January 14, 2018, 07:48 PM   #3
Aguila Blanca
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Quote:
Originally Posted by Kvon2
Does the thumb safety(or the grip safety) block the firing pin when active? In other words, hypothetically, if there was a failure and the hammer dropped but the thumb safety was on(I understand this is HIGHLY unlikely), would the safety prevent the hammer from moving the firing pin?
Absolutely not.

That function is the purpose of the firing pin safety block in the Series 80 system. A 1911 that doesn't have either a Series 80 safety or a variant of the Swartz safety (Kimber and S&W) has nothing to impede the firing pin if the hammer can get to it.
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Old January 14, 2018, 10:04 PM   #4
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Quote:
Absolutely not.

That function is the purpose of the firing pin safety block in the Series 80 system. A 1911 that doesn't have either a Series 80 safety or a variant of the Swartz safety (Kimber and S&W) has nothing to impede the firing pin if the hammer can get to it.
Good post, agree. The following is an example of the Swartz safety, which was on my 9mm Kimber. Pressing on the trigger raises the Swartz safety, which if you notice, has a center notch. The middle notch holds the firing pin in place unless the trigger is pressed. As you can see the Swartz device is spring loaded, located under the rear sight, the spring keeps the system "normally locked".

A series 70 does not have a firing pin block and therefore, is at increased risk of an accidental discharge, either through the hammer dropping, or if the pistol is dropped on its muzzle. If the drop distance is high enough, the firing pin will rebound off the primer with enough energy to ignite the primer, even though the hammer did not hit the firing pin. I think this is the primary reason firing pin blocks were installed in 1911's. This is something that should be understood by everyone who has a series 70 1911, be very attentive not to drop the thing with a round in the chamber.

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Old January 15, 2018, 01:21 AM   #5
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But a number of Series 70-style 1911s have passed California's drop test through the use of a 9mm firing pin and-or titanium firing pin.
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Old January 15, 2018, 06:19 AM   #6
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Quote:
Originally Posted by KyJim
But a number of Series 70-style 1911s have passed California's drop test through the use of a 9mm firing pin and-or titanium firing pin.
True, but this is unrelated to the question that opened this discussion.
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Old January 15, 2018, 06:32 AM   #7
Nathan
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The thumb and grip safeties do not block the firing pin.

The thumb safety does block the hammers travel. That is a separate function from how it locks the sear. In theory, if the sear broke, the hammer is still "locked".

Good firing pin info found above.
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Old January 15, 2018, 07:51 AM   #8
BBarn
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I believe if you look further into the 1911 safety you'll find that the thumb safety alone lacks the proper geometry to block the hammer. The strength of the hammer spring easily overcomes the thumb safety and the hammer will drop, pivoting the thumb safety down with it. Remove the sear and see for yourself.
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Old January 15, 2018, 04:49 PM   #9
Big Shrek
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Quote:
Originally Posted by Slamfire View Post
Good post, agree. The following is an example of the Swartz safety, which was on my 9mm Kimber. Pressing on the trigger raises the Swartz safety, which if you notice, has a center notch. The middle notch holds the firing pin in place unless the trigger is pressed. As you can see the Swartz device is spring loaded, located under the rear sight, the spring keeps the system "normally locked".

A series 70 does not have a firing pin block and therefore, is at increased risk of an accidental discharge, either through the hammer dropping, or if the pistol is dropped on its muzzle. If the drop distance is high enough, the firing pin will rebound off the primer with enough energy to ignite the primer, even though the hammer did not hit the firing pin. I think this is the primary reason firing pin blocks were installed in 1911's. This is something that should be understood by everyone who has a series 70 1911, be very attentive not to drop the thing with a round in the chamber.

Shouldn't you have taken those pics AFTER cleaning it instead of before??
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Old January 15, 2018, 10:09 PM   #10
James K
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The original 1911/A1 is almost impossible to fire if dropped on the muzzle. The reason is that the slide will move back and the recoil spring will absorb the energy that has built up in the firing pin. But, if the pistol has a full length guide rod, the slide cannot move back if the gun lands on the muzzle and the energy is retained by the firing pin, allowing the gun to fire unless there is some other means (e.g., light firing pin or firing pin block) to prevent that.

I might note that sellers and true believers in FLGR's will deny this, but I have tested it many times, enough to convince me that it is the FLGR that is responsible for the firing pin blocks we now have in most new 1911 type pistols.

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Old January 16, 2018, 01:26 AM   #11
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Quote:
Originally Posted by James K
The original 1911/A1 is almost impossible to fire if dropped on the muzzle. The reason is that the slide will move back and the recoil spring will absorb the energy that has built up in the firing pin. But, if the pistol has a full length guide rod, the slide cannot move back if the gun lands on the muzzle and the energy is retained by the firing pin, allowing the gun to fire unless there is some other means (e.g., light firing pin or firing pin block) to prevent that.

I might note that sellers and true believers in FLGR's will deny this, but I have tested it many times, enough to convince me that it is the FLGR that is responsible for the firing pin blocks we now have in most new 1911 type pistols.
A few years ago a respected gentleman named Walt Kuleck set out to test this, and he and his associate (Drake Oldham) found that a 1911 dropped on it's muzzle would fire when dropped from as low as three feet. He put out a video of the testing, and it's probably still out there on the Internet if you search for it. Until I read Walt's report I didn't care if I carried a Series 80 or a non-Series 80. Since his report, I only carry Series 80 pistols.
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