Saturday, March 21, 2009

Colt Cobra 38 Special Trigger Pull

Guest Entry by Mort Snerd!

One of the mysteries of the Spector murder trial is whether or not Lana Clarkson could have had the strength to turn the weapon on herself and fire. Firearms expert James Carroll testified the Colt Cobra requires 11 pounds of pressure to fire the weapon without the hammer pulled back. With the hammer pulled back, it requires 4.5 pounds of pressure to fire the weapon. At my request, T&T's own "firearms expert," Mortie, has been kind enough to outline an example of what 4.5 pounds of trigger pull would feel like to fire the Colt Cobra in the already primed position. Sprocket.

Some experiments to try

Here is a simple experiment you can try at home and be your own “Sprocket” or “Joe Friday”. Realize this is only an experiment and is not an accurate demonstration of firing a real Colt Cobra. It is only to demonstrate the difficulties and problems with human anatomy, specifically tensions and articulations in your hand. No cow heads or chickens will be hurt doing this exercise.

1. Locate a black/blue steel paper clamp as shown below. The 1” size has (at least from Staples) had about 4 pounds of pressure to open it. I measured the force with an old fish scale (spring type) and that would have been a good brook trout.

2. Take a pen of any type but make sure it is thick enough to be clamped securely in the 1” clip. Make sure there is a gap left where the spring closes about 1/8” so the pen is securely held.

3. Now take the clip and using your right hand (or left if you prefer) hold the clip using your index finger and your palm. I have not put the pen in the clip for purposes of clarity.

4. With the clip in this position and pen inserted in the clip, rotate your fist directly in front of your face so that your thumb just touches your nose. This is the distance that hand holding a Colt Cobra 2” barrel would have to be to create the measurements made and confirmed by both the prosecution and defense lawyers for the placement of the gun in Lana Clarkson's mouth.

5. Now squeeze your index finger and let the pen drop free from the clip. Some people cannot squeeze hard enough but most will be able to do this. It is not comfortable and if you have arthritis (like me) it hurts. You will also understand some of the dynamics of the human hand and tensions in your ligaments. Now put your self in the position where a year earlier, both of your wrists were in casts from being broken and then re-injured. It is inconceivable and impossible for me to think that a woman would take this position to commit suicide.



Anonymous said...

That is a very clear piece of information, too bad it wasn't used as a demo during the trial.

ritanita said...

Mort, I couldn't do it. I was in OT a couple of years ago for hand problems and I still haven't recovered my ability to use my hands well.

While there, I was with two people who had broken both wrists. They used a special device to build up strength in their hands which allowed them to "press" weights with their fingers. The rubber bands were for one pound of weight per finger. At five months out from their injuries, "pressing" one pound was difficult. I can't imagine them pressing 4 pounds for a very long time, let alone in the position necessary to fire that gun under optimal conditions. Eleven pounds... never!

I always wondered why that was never brought up.

Anonymous said...

I had a badly broken wrist when I was 12. It took me literally years to regain full strength in my hand. I worked on it constantly. Also, it was tender for several years. So I can imagine that would be a factor with Lana and two broken wrists. I suppose the reason they didn't bring it up is that there are so many variables, and it would take so much court time. Hopefully there is enough other strong evidence to convict.

Anonymous said...

I couldn't do it either, and I'm a 43 year old male. My theory: Mr. Spector couldn't get a certain male organ to 'function' correctly - thus explaining why he chose to walk the 80+ steps to his home to get the blood 'flowing', rather than be dropped off at the back door as he had always done in the past. Upon his failure to perform, Ms. Clarkson decided it was time to go home. A drunken/stoned Spector then blamed Ms. Clarkson for his limpness, and pointed a gun at her - demanding that she 'perform' on the gun.

This would be why Weinberg vigorously objected to photos of Spector's Viagra possession. Remember, he can't stand it when a woman decides it's time to leave. Being the control freak that he is, only he is allowed to determine when a date is over.

Anonymous said...

Do we know for a fact that it was Lana's index finger on the trigger or could it have been her thumb?

CaliGirl9 said...

Mort, that was a very creative way to explain what so many of us have believed about this murder all along.

I've had bilateral carpal tunnel surgery (more than 10 years ago for both) and I couldn't do the experiment without plenty of pain (thanks Sprocket for the little wrist-sized hot/cold pack: I used it after I did this experiment).

It is sad that something this simple could not have been used in the trial.

And as usual, Mort, your knowledge of this physics stuff amazes me!

Anonymous said...

Shooter says:
I am a barely 5ft.,max.100lbs.female
that has sever OP in both wrists. Having on numerous occasions shot a similar handgun can only say your experiment makes no sense. (there is no leverage accounted for ie. gun handle) and where was her other hand?

Sprocket said...

Where were Lana's hands:

We know the back of Lana's wrists were facing the spattering event because of Jamie Lintemoot's testimony of observing spatter on both wrists at the scene.

It would be physically impossible for Lana's finger or thumb to be on the trigger of the weapon and still have the back of her hands be facing the spattering event.

Even with Dr. Di Maio's testimony of how he has seen a suicide victim hold the weapon, that positioning he demonstrated would not account for that spatter on the dorsal (back side) of Lana Clarkson's wrists.

Anonymous said...

The science really tells something there doesn't it? That plus "I think I killed somebody" seems more than enough. The science shows that the back spatter on the wrists shows pretty clearly that she was either defending herself or trying to push him away.

Janet said...

I believe he had pushed it in her mouth and she was trying to push it OUT of her mouth. She pushes on his hand/curled fingers, causing his finger that was already on the trigger to fire the gun. Splatter on back of both her hands.

And then there was his semen on her chest/breast. She wanted to leave but he was forcing a hand job (excuse the bluntness) by jamming a gun in her mouth.

For me that is how it all falls into place.

Sprocket said...


Although I published your comment Janet, I had to immediately respoind your take on the evidence because it is in error. There was no semen found on Lana Clarkson's breast.

There was Spector DNA, but the profile was so weak, the source (speculated by the defense to be saliva) could not be determined by DNA expert Steve Renteria.