Geometry says more but, for practiced shooters, it will be 1/2" or, in some cases, maybe even less!
That’s because something wonderful is happening.
Here’s a little experiment I tried.
- I prepared to dry-fire using a LaserLyte in my 1911 ball gun so I could see where the shot would actually land on the target.
- I lined up the iron sights in the center of the aiming area as usual.
- Then, I watched the front post very carefully as I gently let the gun shift to the *right* just a little, simulating a bad wobble.
- I then made it go “flash!” (Hammer fall.)
When I did this, as the gun moved *right*, the center post moved *left* in the notch of the rear sight (step #3).
And in #4, the laser “strike” on the target moved right also, but only by about the same amount that my hand moved at the end of my arm. In this case, that was about a half inch.
The laser “strike” did *not* move by the angular distance of arm length amplified by the target distance as might be expected from geometry. Instead, it only moved by the same linear amount as my hand moved, about a half inch. Distance to target was irrelevant.
A half inch at the end of my arm was a half inch on the target.
Conversely, when I moved the gun slightly *left* to simulate a bad wobble in that direction, the center post shifted slightly *right* in the rear sight and the laser hit on the target moved to the left also, but only by the distance my hand moved at the end of my arm, again about a half inch.
Obviously, the gun was staying parallel with the original alignment.
It appeared to be working sort of like a pantograph set for 1:1 copying, not like a hinge with a long arm and a gun “out there.”
This was not what I expected!
Astonished at this apparent failing of Euclidean geometry, I put the gun down to write up the result.
As I wrote, I tried to reason out what had to be happening. “Somehow,” I wrote, “I’m keeping the gun aligned on the target even though my eye can’t see it.”
But my brain rebelled at the thought.
“No, this can’t be. Without the eye, there’s no way you can keep the gun lined up on the target when it shifts over like that. It can’t be done.”
I must’ve done something wrong that first time. It just didn’t make any sense.
So I left the keyboard, picked up my 1911 and tried to do it again.
But this time, watching more intensely and thinking through the geometry of what had to be happening, I did *NOT* see the center post move relative to the rear sight!
It didn’t happen in the re-test!
Instead, this time the front and rear sights stayed in alignment the whole time. And when the hammer fell, the laser flash on the target was *much* farther over.
After some head scratching, I came to a “human”, not geometric, conclusion.
What I *think* is happening is there must be some brain/eye/wrist thing that we subconsciously learn to do in Bullseye that explains the first result.
The thought “hand/eye coordination” is nagging at me.
So does the phrase, “Steering the trigger.”
In the first trial, the sights were definitely out of alignment but the gun stayed aimed at the target. The laser strike went where the barrel was aimed. You could say that my eye was taken “out of the loop” *after* initially getting everything lined up.
Finger/wrist/arm/body finished what eye/brain had started.
Apparently my Bullseye practiced body did (or didn’t?) do something so that the result was that the gun remained in alignment on the target.
“Thank you eye/brain, we’ve got it now,” some internal instruction was saying. “You lined up the gun on the center of the target but we can take it from here. Thank you very much.”
But in my second experiment, I kept the brain/eye engaged and “thought too much” about triangles and angles and the immutability of flat-space geometry. In so doing, I forced brain/eye/wrist/etc to “correct” the alignment.
The brain said, “Here, let me *fix* it for you.”
And we all know the result of that.
My High School geometry teacher’s doppelganger is storming about inside my head, spitting and cussing that we’re violating Euclidean space. But at the same time, my inner Earth Mother that understands our physical selves and those squirmy human juicy things is nodding in complete agreement.
“Let it flow,” she murmurs.
Note: In spite of the above, I’m not completely convinced I have this completely figured out. The effect is, at least for me, subtle. I can’t always repeat it. But that may be the result of my admittedly inferior and often erratic ability. Nonetheless, many accomplished (High Master) Bullseye shooters state it as fact, and when you score their targets, there’s no denying those Xs and 10s.