230RN
2A was "political" when it was first adopted.
This reminds me of explaining how much you have to move the rear sight on a gun with a sight radius of 8 inches to move the point of impact four inches at 100 yards (3600 inches).
It's just like using a lever.
It's simple if you draw it out so you can see the proportions:
4 at the target is to 3600 inches as X at the gun is to 8 inches.
Remember proportions in grade school, "this is to that as the other is to so and so?"
4(at the target) ÷(is to) 3600 =(as) X(sight movement) ÷(is to) 8(sight radius)
4/3600 = X/8
transposing the 8 to the other side,
4 x 8 ÷ 3600 = X
x= 0.0088 inches, call it 9 thousandths.
With a rifle with a sight radius of 20 inches, you would have to move the sight
4 is to 3600 as X is to 20
4 / 3600 = X / 20
transposing the 20,
4 x 20 / 3600 = 0.022 inches.
Look at it this way. If the sight radius were 100 yards, to move the point of impact 4 inches at 100 yards, you'd have to move the sight 4 inches as well.
Sort of like a see-saw with the front sight as the pivot point.
And that's why sight radius (on iron-sighted guns) is so critical to accuracy.
If you make a 0.001" eyeball error in aiming a handgun it will mean a much bigger error on target than making that 0.001" eyeball error with a rifle.
Terry, 230RN
It's just like using a lever.
It's simple if you draw it out so you can see the proportions:
4 at the target is to 3600 inches as X at the gun is to 8 inches.
Remember proportions in grade school, "this is to that as the other is to so and so?"
4(at the target) ÷(is to) 3600 =(as) X(sight movement) ÷(is to) 8(sight radius)
4/3600 = X/8
transposing the 8 to the other side,
4 x 8 ÷ 3600 = X
x= 0.0088 inches, call it 9 thousandths.
With a rifle with a sight radius of 20 inches, you would have to move the sight
4 is to 3600 as X is to 20
4 / 3600 = X / 20
transposing the 20,
4 x 20 / 3600 = 0.022 inches.
Look at it this way. If the sight radius were 100 yards, to move the point of impact 4 inches at 100 yards, you'd have to move the sight 4 inches as well.
Sort of like a see-saw with the front sight as the pivot point.
And that's why sight radius (on iron-sighted guns) is so critical to accuracy.
If you make a 0.001" eyeball error in aiming a handgun it will mean a much bigger error on target than making that 0.001" eyeball error with a rifle.
Terry, 230RN
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