The 1911 pistol operates on the Controlled Feed Principle. That is, the round is under direct, positive control of the gun from the time it's loaded into the magazine until the empty case leaves the port.
Not only positive control, but forced control, because the cycle isn't smooth. It's a fairly violent, slam-bang affair, and the opportunity for the gun to lose control of the round is always lurking...always possible...because it's doing its level best to knock it out of control.
This requires that the cartridge is in contact at least two opposing points in its direction of travel. Most important is that it remain in firm contact with the breechface. If if loses contact here...even for a brief instant...it's no longer in control, and if it's not under control, the opportunity for a malfunction increases almost exponentially.
Browning understood this, and he worked to make sure that it didn't happen. Delaying the final release of the cartridge until it was well into the chamber and the rim under the extractor was key, but ol' Mose was the master of redundancy. He backed everything up with a secondary function whenever and wherever he could...just in case the first one was compromised.
In my early days, sittin' at the knee of my father...a toolmaker turned engineer, and my uncle...a retired Navy armorer...I was required to study different functions and explain them in detail as to why they were there...what they did...and what Browning's intent was in including them. Part of my education was studying blueprints.
I was pretty good at figgerin' things out on my own, but when I ran into one little, oft-unseen or unnoticed detail on a slide print one day...I was completely stumped. I made the usual observation as to why the breechface was specified at 89 degrees, 8 minutes to the bottom of the center rail instead of 90 degrees...with zero tolerance allowed...but it was the wrong one.
At this point, I'll add that a surprising number of modern 1911 copies and clones don't adhere to this seemingly trivial, but important spec...checking at a dead-on 90 degrees.
Next is noting that in any machine operation, the smaller the tolerance given, the more critical the dimension. Tool and die makers refer to a .006 inch tolerance...+/-.003 inch...as a football field. To put that into perspective, .003 inch is smaller than the average human hair. Most of the tolerances in an ordnance-spec 1911 pistol are football fields.
Except that breechface angle. There is zero tolerance, plus or minus. 89'8" period.
It's not to compensate for the barrel tilt. If it were, there would be a fairly generous tolerance...at least by tool and die standards. The barrel tilt is slight enough and varies enough that less than a degree from dead square in the breechface angle is really neither here nor there...even if the tolerances were to stack in the wrong direction.
No, the specified angle is about controlled feed. After my uncle shot all my other theories fulla holes...much to my frustration...he told me to take what I knew, and study it until I figured it out. It took me a week of brain-wrackin' agony, but it finally hit me. When it did, it was a facepalm moment. So simple. It had been there all along, and I didn't see it...mainly because I couldn't let go of my preconceived notions. Browning...like an illusionist, fooled me with sleight-of-hand and that barrel tilt.
Once I started thinking of what happened before the barrel went to battery, it literally jumped off the page at me.
My reward was a worn-out 1943 Ithaca of my very own to have and to hold and to shoot until it fell apart if I chose...after I rebuilt it, of course. I did, and I still have it...and it still runs like a Singer sewing machine on the rare occasion that I drag it out of the mothballs. (No pun intended)
So, go put your thinkin' caps on. Let's see how many can crack Browning's code.
Not only positive control, but forced control, because the cycle isn't smooth. It's a fairly violent, slam-bang affair, and the opportunity for the gun to lose control of the round is always lurking...always possible...because it's doing its level best to knock it out of control.
This requires that the cartridge is in contact at least two opposing points in its direction of travel. Most important is that it remain in firm contact with the breechface. If if loses contact here...even for a brief instant...it's no longer in control, and if it's not under control, the opportunity for a malfunction increases almost exponentially.
Browning understood this, and he worked to make sure that it didn't happen. Delaying the final release of the cartridge until it was well into the chamber and the rim under the extractor was key, but ol' Mose was the master of redundancy. He backed everything up with a secondary function whenever and wherever he could...just in case the first one was compromised.
In my early days, sittin' at the knee of my father...a toolmaker turned engineer, and my uncle...a retired Navy armorer...I was required to study different functions and explain them in detail as to why they were there...what they did...and what Browning's intent was in including them. Part of my education was studying blueprints.
I was pretty good at figgerin' things out on my own, but when I ran into one little, oft-unseen or unnoticed detail on a slide print one day...I was completely stumped. I made the usual observation as to why the breechface was specified at 89 degrees, 8 minutes to the bottom of the center rail instead of 90 degrees...with zero tolerance allowed...but it was the wrong one.
At this point, I'll add that a surprising number of modern 1911 copies and clones don't adhere to this seemingly trivial, but important spec...checking at a dead-on 90 degrees.
Next is noting that in any machine operation, the smaller the tolerance given, the more critical the dimension. Tool and die makers refer to a .006 inch tolerance...+/-.003 inch...as a football field. To put that into perspective, .003 inch is smaller than the average human hair. Most of the tolerances in an ordnance-spec 1911 pistol are football fields.
Except that breechface angle. There is zero tolerance, plus or minus. 89'8" period.
It's not to compensate for the barrel tilt. If it were, there would be a fairly generous tolerance...at least by tool and die standards. The barrel tilt is slight enough and varies enough that less than a degree from dead square in the breechface angle is really neither here nor there...even if the tolerances were to stack in the wrong direction.
No, the specified angle is about controlled feed. After my uncle shot all my other theories fulla holes...much to my frustration...he told me to take what I knew, and study it until I figured it out. It took me a week of brain-wrackin' agony, but it finally hit me. When it did, it was a facepalm moment. So simple. It had been there all along, and I didn't see it...mainly because I couldn't let go of my preconceived notions. Browning...like an illusionist, fooled me with sleight-of-hand and that barrel tilt.
Once I started thinking of what happened before the barrel went to battery, it literally jumped off the page at me.
My reward was a worn-out 1943 Ithaca of my very own to have and to hold and to shoot until it fell apart if I chose...after I rebuilt it, of course. I did, and I still have it...and it still runs like a Singer sewing machine on the rare occasion that I drag it out of the mothballs. (No pun intended)
So, go put your thinkin' caps on. Let's see how many can crack Browning's code.