[Reiver]

“With the hammer de-cocked on a loaded chamber, the gun was able to detonate a primer "without a pull of the trigger when the hammer was struck directly," which is normal for this type of revolver, the report stated.”

That is not what took place.... as stated above all original Colts hammers rested near the primer of a loaded cylinder..fully forward, not cocked. If you struck the hammer spur hard, like with a rock, or dropped the weapon landing on its hammer it could discharge. However, you had to hit the hammer with something for this to happen...just holding it in your hand would do nada. Striking the hammer with the heel of your hand would likely give you a nice bruise but would not discharge a round unless you were the Hulk.

Many carried a Colt, myself included, with 5 rounds chambered and the hammer down on an empty chamber.

When cocked, as numbnutz did, this event is not in play. You can hit the hammer when cocked and the trigger sear will still hold it in place.

As the investigation showed...when at full cock the hammer would only fall when the trigger was pulled....numbnutz cocked the weapon and admitted as much. He pulled the trigger.