There is the common problem that has been talked about at length. "I've got 1/4" @ 100 yds. turret and MIL DOT reticle, how do I figure my drop for both?" Well this is what I did. Keep in mind this is not field math. This is sitting at the table when you have time math.
When you need to make a dope chart to affix to your rifle. Your drop in inches may have come from ballistics calculators or you may have shot your load of choice at the various ranges. Whatever be the case, you need to convert your inch measurement to MOA turret adjustment as well as MIL hold for elevation and windage, because we don't care what the measurement of inches are while in the field. I may have done this the hard way, but this is the way I figured it out. I had a standard tape measure that read in 1/16" and I fired my rounds at the various ranges to find my drop in inches because I didn't have a chronograph at the time.
In case you fogot one of the math classes years ago. The way to convert a fraction to a decimal is the numerator (top number) divided by the denominator (the bottom number).
Example: K.I.S.S. Keep It Simple Stupid!
For 1/2 (half) 1 divided by 2 is .5
<span style="text-decoration: underline">Converting Inches in drop to ¼" @ 100 turret</span>
<span style="font-weight: bold">FIRST</span> .25” (1/4”) x .01 (1/100) of the yardage = ¼ value (click value)
Example: For 250 yards .25” (1/4”) x 2.5 = .625” (5/8”) click value
For 350 yards .25” (1/4”) x 3.5 =.875” (7/8”) click value
<span style="font-weight: bold">SECOND</span> Take the drop in inches ÷ the click value
Example: My 300 yard drop is 3 ¾” (3.75”) ÷ ¾” (.75” click value) = 5 clicks
But wait! 4 clicks equals 1 , on the ¼ turret, so it’s 1 ¼. Therefore I can move the turret to the number 1 plus 1 click a.k.a. 1 ¼.
If you have an 1/8" turret you would replace the ¼” or .25” with 1/8” or .125”
<span style="text-decoration: underline">Converting Inches in drop to MIL Holdover</span>
<span style="font-weight: bold">FIRST</span> 3.6” (Mil to Mil @ 100 yds.) x .01 (1/100) of the yardage = MIL value @ the prescribed yardage.
Example: For 250 yards 3.6” (approx. 3 5/8”) x 2.5 = 9”
For 300 yards 3.6” x 3 = 10.8” (10 13/16”)
<span style="font-weight: bold">SECOND</span> Divide the MIL value by the desired divisions. I recommend ¼ MIL or 1/10 MIL
Example: For 250 yards 1 MIL is 9” (3.6” x 2.5=9”) ÷ 4 = 2.25” per ¼ MIL
9” ÷ 10 = .9” per 1/10 MIL
For 300 yards 1 MIL is 10.8” (3.6” x 3) ÷ 10 = 1.08” per 1/10 MIL round to 1” per 1/10 MIL
<span style="font-weight: bold">THIRD</span> Inches in drop @ the prescribed range ÷ the selected MIL increment from the second step = MIL holdover
Example: For 250 yards my drop is 1 7/8” a.k.a. 1.875” a ¼ MIL is 2 ¼” a.k.a. 2.25” so you would hold ¼ MIL there even though it is a little high it is closer than a no hold.
1 7/8” a.k.a.1.875” ÷ .9 (value of 1/10 MIL) = 2/10ths MIL because 1/10 MIL represents .9” x 2 = 1.8”
Note: If your number comes out above ten then that is a full MIL plus the leftover.
Example: My 400 yard drop is 20”
1MIL = 3.6” x 4 = 14.4”
14.4” ÷ .1= 1.44” per 1/10 MIL
20” ÷ 1.44” = 13.88 tenths of a MIL
10 tenths equals 1 plus rounded .388 to .4 MIL hold over is 1.4 MIL
Rifle: Savage Model 12FV, 26" Savage barrel.
Optic: Millett 4.5-16 x 40 1/4 MOA turrets.
Case: Once fired Remington
Trim: 1.90"
Primer: Winchester Large Rifle
Powder: H Varget 36.0 gr.
Bullet: 55gr. Sierra Game King HPBT
O.A.L.: 2.360"
TURRET, MIL HOLDOVER
100yd. -3/4, -.2
150yd. -1/2, -.2
200yd. ZERO, 0
250yd. +3/4, +.2
300yd. +1 1/4, +.4
350yd. +2 3/4, +.8
400yd. +5, +1.4
I'm sorry that it looks a little cluttered it won't "clean up" on the post thread like it will in a word document.
When you need to make a dope chart to affix to your rifle. Your drop in inches may have come from ballistics calculators or you may have shot your load of choice at the various ranges. Whatever be the case, you need to convert your inch measurement to MOA turret adjustment as well as MIL hold for elevation and windage, because we don't care what the measurement of inches are while in the field. I may have done this the hard way, but this is the way I figured it out. I had a standard tape measure that read in 1/16" and I fired my rounds at the various ranges to find my drop in inches because I didn't have a chronograph at the time.
In case you fogot one of the math classes years ago. The way to convert a fraction to a decimal is the numerator (top number) divided by the denominator (the bottom number).
Example: K.I.S.S. Keep It Simple Stupid!
For 1/2 (half) 1 divided by 2 is .5
<span style="text-decoration: underline">Converting Inches in drop to ¼" @ 100 turret</span>
<span style="font-weight: bold">FIRST</span> .25” (1/4”) x .01 (1/100) of the yardage = ¼ value (click value)
Example: For 250 yards .25” (1/4”) x 2.5 = .625” (5/8”) click value
For 350 yards .25” (1/4”) x 3.5 =.875” (7/8”) click value
<span style="font-weight: bold">SECOND</span> Take the drop in inches ÷ the click value
Example: My 300 yard drop is 3 ¾” (3.75”) ÷ ¾” (.75” click value) = 5 clicks
But wait! 4 clicks equals 1 , on the ¼ turret, so it’s 1 ¼. Therefore I can move the turret to the number 1 plus 1 click a.k.a. 1 ¼.
If you have an 1/8" turret you would replace the ¼” or .25” with 1/8” or .125”
<span style="text-decoration: underline">Converting Inches in drop to MIL Holdover</span>
<span style="font-weight: bold">FIRST</span> 3.6” (Mil to Mil @ 100 yds.) x .01 (1/100) of the yardage = MIL value @ the prescribed yardage.
Example: For 250 yards 3.6” (approx. 3 5/8”) x 2.5 = 9”
For 300 yards 3.6” x 3 = 10.8” (10 13/16”)
<span style="font-weight: bold">SECOND</span> Divide the MIL value by the desired divisions. I recommend ¼ MIL or 1/10 MIL
Example: For 250 yards 1 MIL is 9” (3.6” x 2.5=9”) ÷ 4 = 2.25” per ¼ MIL
9” ÷ 10 = .9” per 1/10 MIL
For 300 yards 1 MIL is 10.8” (3.6” x 3) ÷ 10 = 1.08” per 1/10 MIL round to 1” per 1/10 MIL
<span style="font-weight: bold">THIRD</span> Inches in drop @ the prescribed range ÷ the selected MIL increment from the second step = MIL holdover
Example: For 250 yards my drop is 1 7/8” a.k.a. 1.875” a ¼ MIL is 2 ¼” a.k.a. 2.25” so you would hold ¼ MIL there even though it is a little high it is closer than a no hold.
1 7/8” a.k.a.1.875” ÷ .9 (value of 1/10 MIL) = 2/10ths MIL because 1/10 MIL represents .9” x 2 = 1.8”
Note: If your number comes out above ten then that is a full MIL plus the leftover.
Example: My 400 yard drop is 20”
1MIL = 3.6” x 4 = 14.4”
14.4” ÷ .1= 1.44” per 1/10 MIL
20” ÷ 1.44” = 13.88 tenths of a MIL
10 tenths equals 1 plus rounded .388 to .4 MIL hold over is 1.4 MIL
Rifle: Savage Model 12FV, 26" Savage barrel.
Optic: Millett 4.5-16 x 40 1/4 MOA turrets.
Case: Once fired Remington
Trim: 1.90"
Primer: Winchester Large Rifle
Powder: H Varget 36.0 gr.
Bullet: 55gr. Sierra Game King HPBT
O.A.L.: 2.360"
TURRET, MIL HOLDOVER
100yd. -3/4, -.2
150yd. -1/2, -.2
200yd. ZERO, 0
250yd. +3/4, +.2
300yd. +1 1/4, +.4
350yd. +2 3/4, +.8
400yd. +5, +1.4
I'm sorry that it looks a little cluttered it won't "clean up" on the post thread like it will in a word document.
