Yeah--i do screw that up now and then...It makes one look even smarter to use the correct word, which is subtention.
Yeah--i do screw that up now and then...It makes one look even smarter to use the correct word, which is subtention.
I'm game.I'd like to see ya range me with your fancy electronic doohicky while my "crude, inaccurate, imprecise"ly range estimated rounds are dancing ever closer. Hold still now...
About 200 yards beyond your MPBR, and just over the top of your head.I'm game.
What distance are you talking about?
What's your hold at that distance?
About 200 yards beyond your MPBR, and just over the top of your head.
Sure they hit things 100 years ago but distance records are being set everyday because of technology.About 200 yards beyond your MPBR, and just over the top of your head.The point being that people hit things with rifles BEFORE the technology evolved. Does the new stuff make it easier? Of course. But does that mean that one shouldn't understand and embrace the basics that have begotten todays tools? Hell no I say. The naysayers remind me of my nephew who doesn't know how to make a call on a rotary phone.
Allow me to ramble for a bit, it will be worth it if you shoot open sight rifles much.
We all know that one minute of angle is 1.047" per 100 yards. But most don't know why this is.
100 yards is 300 feet. 300 X 12 = 3600 inches.
3600 X pi (because it's a radius around you) = 11,309.73355
11,309.73355 / 180 (degrees in radius) = 62.83185307 inches per degree
62.83185307 / 60 (minutes in a degree) = 1.047197551 inches per MOA
So what does it matter?
You've got this front sight hanging out there. If you've got a standard AR front sight, it's .072".
It's also a given distance from your eyeball, depending on your cheek weld. Lets go with 23.5 inches because that's my distance with an A2 rifle.
23.5 X pi = 73.82742736
73.82742736 / 180 = .410152374
.410152374 / 60 = .006835873
.072 (front sight width) / .006835873 = 10.53267081
So i know my front sight subtends 10.5 MA
So:
Distance from eye to front sight times pi = radius.
Answer from line one (radius) divided by 180 - one angle.
answer from line two (angle) divided by 60 minutes = one MOA
Front sight width divided by one MOA = front sight width in MOA.
I'd like to see ya range me with your fancy electronic doohicky while my "crude, inaccurate, imprecise"ly range estimated rounds are dancing ever closer. Hold still now...
you must not have seen the Mosin Nagant Marksmanship Card.I use this math often to demonstrate how terribly coarse in aiming precision iron sights really are.
I would never pretend a front sight could effectively be employed as a rangefinding device - ever. Holding that 10.5moa wide blade on target is one thing, but it’s laughable to think a guy can accurately measure multiples (and fractional multiples) of the blade width on target to precisely range a target is ridiculous.
Especially considering the illusory zoom of a front sight blade as viewed through an aperture. Varying environmental brightness and varying aperture diameters can make the front blade APPEAR larger or smaller against the target.
Let’s say I have a round gong at 100 yards. Just about the same apparent width as the front sight blade. Is it 10”, or 12”? Can you tell? So flipping that script - if I have a 30” gong at an unknown distance, again, about the same apparent width as the gong. Is it just a little bit smaller, just as the 10” gong was in the first example, or is it a teeny bit bigger, as the 12” gong was... because the difference in misjudging, misreading the relative size, is 280 yards versus 340. I generally don’t care to misjudge the range to my target by 60 yards. Now let’s say it’s a 4-5” wide prairie dog... it only covers ~1/3 the width of the front sight blade. Is it really 1/3 the width, or 1/4? Or 40%? Is the prairie dog 4”wide? Or 5? Or maybe it’s 4 5/8”.
The only conditions in which such crude, inaccurate, imprecise systems can work are when there’s a massive margin for error, effectively, within the maximum point blank range of the cartridge, aka, where rangefinding isn’t pertinent.
100 yards is 300 feet, is 3600 inches.Alright, I know this is going to sound pedantic, but this is a pet peeve. I cringe when I hear someone say "one minute of angle is 1.047" at 100 yards".
Minutes of angle are units of angular measurement. A minute of angle is 1/60 of one degree of angular measurement.
An inch is a unit of linear measurement. A unit of angular measurement cannot become a unit of linear measurement and vice verse.
One minute of angle subtends one minute of arc on the circumference of a circle the center of which is at the vertex of that angle of minute. If the radius of that circle is 100 yards, the length of the arc subtended is 1.047". Note that this is a measurement of arc length, not a straight vertical distance as we are usually measuring off a target. But because the unit of angular measurement is so small, the curvature of the arc can be disregarded.
The only conditions in which such crude, inaccurate, imprecise systems can work are when there’s a massive margin for error, effectively, within the maximum point blank range of the cartridge, aka, where rangefinding isn’t pertinent.
100 yards is 300 feet, is 3600 inches.
3600 inches x TAN(1/60)= 1.0471975 inches
so much for that.