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joostin4
04-29-2011, 3:08 PM
From what I understand a firing pin block safety blocks the hammer from striking the primer unless the trigger is pulled.

Does this mean that if the hammer hits the primer without the trigger actually being pulled, the gun will not fire? So if a gun were dropped on the ground accidentally with the hammer cocked, there is no chance of accidental discharge?

Also, if a firing pin block disables discharge without trigger pull, then why would it be dangerous to manually uncock a 1911? Wouldn't manually uncocking the hammer not set off the 1911 even if one were to slip and accidentally let the hammer fall?

I am quite confused...

Brandon04GT
04-29-2011, 3:10 PM
From what I understand a firing pin block safety blocks the hammer from striking the primer unless the trigger is pulled.

Does this mean that if the hammer hits the primer without the trigger actually being pulled, the gun will not fire? So if a gun were dropped on the ground accidentally with the hammer cocked, there is no chance of accidental discharge?

Also, if a firing pin block disables discharge without trigger pull, then why would it be dangerous to manually uncock a 1911? Wouldn't manually uncocking the hammer not set off the 1911 even if one were to slip and accidentally let the hammer fall?

I am quite confused...

Manually decocking a 1911 (as with most other guns) requires you to pull on the trigger...

J.D.Allen
04-29-2011, 3:39 PM
From what I understand a firing pin block safety blocks the hammer from striking the primer unless the trigger is pulled.

Does this mean that if the hammer hits the primer without the trigger actually being pulled, the gun will not fire? So if a gun were dropped on the ground accidentally with the hammer cocked, there is no chance of accidental discharge?

Also, if a firing pin block disables discharge without trigger pull, then why would it be dangerous to manually uncock a 1911? Wouldn't manually uncocking the hammer not set off the 1911 even if one were to slip and accidentally let the hammer fall?

I am quite confused...

Yes, you seem to be confused. Let me see if I can help.

A Firing Pin Block (FPB) is used is semi-automatic pistols. In a semi-automatic pistol, the hammer does not hit the primer, the firing pin does. The hammer strikes the firing pin. The point of the FPB, like its name indicates, is to block the firing pin from hitting the primer of the round unless the trigger is pulled.

So yes, if you drop the weapon or in some other way drop the hammer on a live round without pulling the trigger, the weapon will not fire.

Manually decocking a 1911 requires pulling the trigger, therefore disabling the FPB and allowing the weapon to fire if you accidentally let the hammer slip.

Also, many 1911's do not have FPB's anyway.

Does that help to clear things up?

Cyc Wid It
04-29-2011, 4:43 PM
Colt Series 80 style FPB is probably the "best." Conversely, the Schwartz are the most hated. With single shot exemptions, no reason to have either if you don't care for them.

elSquid
04-29-2011, 7:47 PM
http://www.defensivecarry.com/gallery/data/500/series80fpblock.jpg

There is no reason to "decock" a 1911 over a live round. Either keep it cocked-n-locked, or unload the firearm ( confirm empty chamber ) and just pull the trigger while it's pointed in a safe direction...

-- Michael

joostin4
05-01-2011, 3:30 PM
Ok, from what I'm understanding from the responses,

The firing pin block disables discharge unless the trigger is pulled.


So in other words,

Any gun without a firing pin WILL discharge when the hammer is accidentally released (for example if the gun were accidentally dropped on the ground while cocked).

ojisan
05-01-2011, 3:52 PM
"Any gun without a firing pin block WILL discharge when the hammer is accidentally released..."

Not exactly.
A FPB is only one of many ways way to add a safety mechanism to prevent accidental misfires.
The FPB is a good design and method to prevent the firing pin from striking the primer due to inertia or a hammer blow such as in a drop situation.
Some designs use a very strong return spring on the firing pin that can only be overcome by a proper direct hammer blow.
Many guns, even older ones and revolvers, use a variety of methods to make them more "drop-safe".
The 1911 design, for example, has a large extra safety notch cut into the hammer base that will catch the hammer with the sear at half fall if the trigger is not pulled.

iareConfusE
05-01-2011, 4:03 PM
Ok, from what I'm understanding from the responses,

The firing pin block disables discharge unless the trigger is pulled.


So in other words,

Any gun without a firing pin WILL discharge when the hammer is accidentally released (for example if the gun were accidentally dropped on the ground while cocked).

It's never one or the other. Just because you have no FPB doesn't mean that your gun WILL discharge when it falls to the ground. Similarly, your gun may still discharge even with a FPB. Redundant firearm safeties are just... redundant.

They are just one of many ways to prevent accidents, but they are not fool proof, and malfunctions can and have happened with safeties before. Don't rely on any firearm safety device to prevent accidents or negligent discharges. Your trigger finger and common sense are your best safeties. Use them, wisely.

bwiese
05-01-2011, 4:22 PM
Newer revolvers, including post-1973 Ruger single-action revolvers, many late 90s and onward S&W revolvers and Ruger GP/SP revolvers use a 'transfer bar' safety system. [Note: above dates uncertain and there are probably exceptions.]

The hammer never directly contacts the firing pin on a transfer bar revolver. In fact, if the transfer bar is not 'in position' (only achievable thru actual trigger pull action) there is no way for the hammer to hit the recessed firing pin: the transfer bar is what couples the motion from the falling hammer into the firiing pin.

JanG
05-01-2011, 5:45 PM
there are many 1911s that supposedly passed california's dreaded drop safety test that don't have firing pin safeties. rock islands, nighthawks, etc. springfield uses a titanium firing pin (and smith & wesson just released one too).