O-Frame Cocked and Locked

[WKC]

I have hear many uninformed opinions about the safety of the O-Frame being carried in a cocked and locked configuration. Here is an unfortunate experience with a brand new Springfield. The story about what happened to his O-Frame starts on post #43. In post #46, he states that he found the gun in the cocked and locked configuration which is how he left it in the box after picking it up. High speed impact off the back of a bike onto the freeway and the hammer did not move.

[BonoVox]

I think there is lots and lots of experience here on the site. Probably adding up to many decades of time of people carrying O Frames cocked and locked with 100% safety rating. Though I do not carry one, I would not have a second of thought about the safety in carrying one cocked and locked.

Like all guns 99% of the safety is with the opperator.

[WKC]

Originally Posted by BonoVox

Like all guns 99% of the safety is with the opperator.

Very true.

I just want to make clear that my comment about uninformed opinion is not directed at any forum members.

[X-ffdo]

1911s have been dropped out of airplanes and helicopters in cocked and locked conditions, they have prevailed.

[Dan M.]

Originally Posted by WKC

I have hear many uninformed opinions about the safety of the O-Frame being carried in a cocked and locked configuration. Here is an unfortunate experience with a brand new Springfield. The story about what happened to his O-Frame starts on post #43. In post #46, he states that he found the gun in the cocked and locked configuration which is how he left it in the box after picking it up. High speed impact off the back of a bike onto the freeway and the hammer did not move.

What an awful story.

[GunSlut]

This is a perfect example of when a guy needs to know when to zip and how to zip.

This is a clue to read the thread. It is one hell of a story!

[Hoser]

I agree, a cocked and locked. .45 is safe, but the below link makes for interesting reading!

Spontaneous Discharge of a Firearm in an MR Imaging Environment -- Beitia et al. 178 (5): 1092 -- American Journal of Roentgenology

[WKC]

This incident was a topic of discussion before. I still do not understand or agree with the conclusion about how the round was discharged. The theory of how the magnetic field caused the firing pin safety to disengage just does not make sense. If the magnetic field had an influenced on the firing pin safety, it would also have an influence on the slide surrounding it. So why would the firing pin safety move relative to the slide?

Since the incident occurred with an O-Frame, some may think that an accident discharge of this type can only happen with the O-Frame design. What ever happened to this gun to cause it to fire would have cause guns of other design to fire as well. There are other pistols with the same inertial firing pin and firing pin safety design. It is not unique to the O-Frame.

One aspect of the O-Frame that is not a common design feature among other pistols is the safety locking the slide. In this case, the slide was locked and the AD did not cause another round to be chambered.

I wonder what was on JMB's mind when he decided to lock the slide with the manual safety?

[inboost]

WKC,

I'm with you, this doesn't add up. I'm fairly certain we've not gotten the whole story on the MRI ND. However I do find the guy on the bike's story easy to believe. Sad, but true. At least it had a happy ending!

My take on the MRI ND: The firing pin safety was probably not installed at the time of impact.

How many people fault this device as degrading the reliability of the basic 1911 design? I'd guess more than we care to admit. The firing pin safety is easily removed during even a routine slide strip and is not required for the gun to continue to function.

The hit mark on the nose of the muzzle combined with the ND suggest that inertia was indeed the culprit. However, the firing pin safety is on a perpendicular axis to the bore, so if anything the sudden deceleration would have decreased it's ability to move. Think about the timing sequence that would have been required. The firing pin safety would have had to have been sucked up out of the way before the impact. The only way I see this happening is if the gun left the guy's hand in a flat spin such that centripetal motion could have encouraged the firing pin safety to seek the top of the slide. Then at the exact moment of impact the gun was perfectly aligned such that muzzle hit the MRI core square. All this from 3 feet away! I feel it would have to have been whipped out of his hand at a fairly decent angular velocity to retract that safety. Even if the gun pin-wheeled about his hand to head for the core I don't think it would have been experiencing the required angular acceleration required to load the safety beyond the spring capacity for any length of time. At 3 feet from start to finish there couldn't have been much time between the gun leaving his grasp to when it hit the MRI core, so all the velocities would have been 'relatively' low. Let's not also forget that the bore that the safety rides in is rough and unfinished and likely to have been a bit dirty too. All of these would have worked against it's moving under external forces...

[X-ffdo]

Murphy was there!

[hygyliac]

Inboost's explaination makes lots of sense. I looked at the enlarged picture of the 1911 and the barrel's direction in relation to the MRI tunnel. Are there multi lines of magnetic force generated by the machine? Are they circular and/or linear lines of force? The 1911 appears to have its barrel facing more or less into the tunnel. If you look at the picture, imagine a magnetic line of force traveling in a circular counterclockwise direction. That could explain the reason for firing pin block being moved into the slide. At the same time, linear lines of force (heading into the tunnel) could be pulling the firing pin forward. This wouldn't have to happen at the exact same time. It would be similar to stretching a rubber band and then releasing one end. The firing pin could be under continuous pressure to move forward. And it probably did ONCE the block was moved the required distance inside the slide. Is there anyone out there that is in the profession and is familiar with how the machine works?
For an experiment, I took apart one of my commanders. The firing pin does react to the refrigerator magnet. Does any one have one of the new models with the firing pin block to see if it also reacts to a magnet also?

[WKC]

The firing pin is steel so it will be influenced by a magnetic field. However, so is the slide. My point is that putting two ferrous objects in a magnetic field will not result in one moving relative to the other. They will both be influenced by the magnetic field and may not be able to move relative to each other. Try putting the firing pin in the tunnel without the spring and then put a magnet on the slide and see if you can move the firing pin.

[hygyliac]

Originally Posted by WKC

The firing pin is steel so it will be influenced by a magnetic field. However, so is the slide. My point is that putting two ferrous objects in a magnetic field will not result in one moving relative to the other. They will both be influenced by the magnetic field and may not be able to move relative to each other. Try putting the firing pin in the tunnel without the spring and then put a magnet on the slide and see if you can move the firing pin.

Good idea! Tried it and the firing pin did move, but I think that my refrigerator magnet wasn't powerful enough to move the weight of the slide thus resulting in only the firing pin reacting. The pin was in the slide and the slide placed in the upright position on a flat smooth marble table (don't tell my wife). Magnet was slowly placed in front of firing pin hole. Knob of firing pin appeared at breach of the opening, just barely breaking the vertical plane. Re-analyzing your statement, I think you are correct. It MAKES SENSE both slide and firing pin should move as a unit, akin to gravity pulling with the same constant on objects both large and small.
I'm out, next batter to the plate!

[kydave]

While not an expert by any means, I have had an passing interest in handguns for many years and read and subscribed to a number of firearms publications over the years.

Until recently I'd never noticed references to O-Frames as pertains to what most people just call 1911 and variants. Is this a relatively new way that people in the know refer to certain Colt (is it just Colt?) frames?

Thanks,
Dave

[hygyliac]

Hi Ky, the terms as far as I know are basically interchangeable. Most people who do their own modifications or have been to gunsmithing classes are refering to it as "O" frame. I'm from the old school and "1911" is how I refer to it. I'd be interested to know if it is a technical term, like J frame, L frame etc. Did it start being used when the frames were strengthen or when the new methods of production became the norm? Good question, Ky!!!!! If its okay with you guys, can I still call it a "1911"