wildcard

05-09-2008, 7:55 AM

This is just a general observation..

When milling, I've realized that you have to be either very precise or lucky for objects that read less than 2 MILS on your scope. For those of you who use a chart that increment at .25 MILS (I assume most do), listen up.

Lets just say for example you have a target that is 10" (silhouette of a average human head perhaps) and you read the MILS to be .75 because thats what it looks like and you have the measurement on your chart. If you do the math or look it up in your chart, you'll find that the target is 370 yds away.

Now let's say you simply rounded to .75 MILS because it was convenient but the MIL reading was actually more like .70 MILS. If you do the math on that, you'll find that the target is actually 396 yds away.

That's a difference of 26 yds or .75 MOA of adjustment if you're shooting a 168 SMK out of a .308. Assuming your gun is capable of 1 MOA accuracy resulting in a 1.5" radius and your miscalculation of 2.25", you'd be off by about 3.75".. almost enough for a miss. You get the point though.

Moral of the story, get a calculator and know your formulas. I picked up a Casio databank calculator watch for $27 shipped with a 10 year battery. I can store 25 lines of data in it and calculate on the fly.

http://www.casio.com/products/Timepiece/Databank/DBC32_Series/product/DBC32-1A/

Edited to add: It also comes in handy for object sizes which don't fall into one of the categories on the chart.

When milling, I've realized that you have to be either very precise or lucky for objects that read less than 2 MILS on your scope. For those of you who use a chart that increment at .25 MILS (I assume most do), listen up.

Lets just say for example you have a target that is 10" (silhouette of a average human head perhaps) and you read the MILS to be .75 because thats what it looks like and you have the measurement on your chart. If you do the math or look it up in your chart, you'll find that the target is 370 yds away.

Now let's say you simply rounded to .75 MILS because it was convenient but the MIL reading was actually more like .70 MILS. If you do the math on that, you'll find that the target is actually 396 yds away.

That's a difference of 26 yds or .75 MOA of adjustment if you're shooting a 168 SMK out of a .308. Assuming your gun is capable of 1 MOA accuracy resulting in a 1.5" radius and your miscalculation of 2.25", you'd be off by about 3.75".. almost enough for a miss. You get the point though.

Moral of the story, get a calculator and know your formulas. I picked up a Casio databank calculator watch for $27 shipped with a 10 year battery. I can store 25 lines of data in it and calculate on the fly.

http://www.casio.com/products/Timepiece/Databank/DBC32_Series/product/DBC32-1A/

Edited to add: It also comes in handy for object sizes which don't fall into one of the categories on the chart.