About 20 years ago, give or take, I became acquainted with a savvy old pistolsmith up in Maryland on THR. He performed a demonstration that many would consider insane.
In an effort to show that Kuhnhaunsen's Balanced Thrust Vector description was sheep dip...and it was...by using steel rod with the end lathe turned to closely match the nose profile of a 250 grain .45 RN bullet. He threaded the barrel,and used a bolt to secure it.
And, then he fired the gun. Predictably, nothing happened. The slide didn't move and the only indication that gun had fired was a wisp of smoke escaping around the breech and a hissing sound.
Some of the members over there did all but call him a liar, until one of them duplicated it...and then he apologized.
So, he was satisfied that he'd disproved Jerry K's description by showing that if the bullet doesn't move, the slide doesn't move.
The thing that he didn't...couldn't grasp...was WHY the slide didn't move. In his rush to make a monkey out of Kuhnhausen, he inadvertently created a system of balanced forces, and balanced forces don't result in movement. Only when forces become unbalanced does movement occur.
So, why didn't the slide move? I'm glad you asked.
The bullet was pushing on the rod. The rod was pushing on the bolt. The bolt was threaded into the barrel, so by default...the bullet was pushing the barrel forward at the same time that equal forces were trying to drive the slide rearward.
Because the barrel was locked to the slide, the slide didn't move...not because the bullet didn't move...but because the barrel COULDN'T move. It was held in place by a force that was equal to the force acting on the slide.
Whatever force resists the barrel's rearward movement, also resists the slide's rearward movement. That is the crux of the locked breech system.
In an effort to show that Kuhnhaunsen's Balanced Thrust Vector description was sheep dip...and it was...by using steel rod with the end lathe turned to closely match the nose profile of a 250 grain .45 RN bullet. He threaded the barrel,and used a bolt to secure it.
And, then he fired the gun. Predictably, nothing happened. The slide didn't move and the only indication that gun had fired was a wisp of smoke escaping around the breech and a hissing sound.
Some of the members over there did all but call him a liar, until one of them duplicated it...and then he apologized.
So, he was satisfied that he'd disproved Jerry K's description by showing that if the bullet doesn't move, the slide doesn't move.
The thing that he didn't...couldn't grasp...was WHY the slide didn't move. In his rush to make a monkey out of Kuhnhausen, he inadvertently created a system of balanced forces, and balanced forces don't result in movement. Only when forces become unbalanced does movement occur.
So, why didn't the slide move? I'm glad you asked.
The bullet was pushing on the rod. The rod was pushing on the bolt. The bolt was threaded into the barrel, so by default...the bullet was pushing the barrel forward at the same time that equal forces were trying to drive the slide rearward.
Because the barrel was locked to the slide, the slide didn't move...not because the bullet didn't move...but because the barrel COULDN'T move. It was held in place by a force that was equal to the force acting on the slide.
Whatever force resists the barrel's rearward movement, also resists the slide's rearward movement. That is the crux of the locked breech system.
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