Range Report Not understanding something in JBM Ballistics

[shane45]

I misplaced my range card made from actual shooting so on my way out the door I popped on to JBM for a quick card to be close at least. The thing that is tripping me up is the output. I have a mil/mil scope. When I try and get values in the output, even in the program its self they dont match up. For example, Ill get say 29cm for a value at 300 but a mil value of 1.1 for 300???? What am I doing wrong in the program or not understanding?

Example:
Trajectory μCard
Range Drop Wind Lead
(yd) <span style="font-weight: bold"><span style="color: #FF0000">(mil) (cm)</span></span> (mil) (cm) (mil) (cm)
100 -0.0 -0.0 0.0 0.0 5.2 47.5
200 -0.4 -7.9 0.2 2.8 5.3 97.8
300 <span style="font-weight: bold"><span style="color: #FF0000">-1.1 -29.1</span></span> 0.3 8.7 5.5 151.2
350 -1.4 -45.1 0.4 12.9 5.6 179.2
400 -1.8 -65.1 0.5 18.0 5.7 208.0
450 -2.2 -89.3 0.6 24.0 5.8 237.7
500 -2.6 -117.9 0.7 30.9 5.9 268.4
525 -2.8 -134.0 0.7 34.8 5.9 284.1
550 -3.0 -151.4 0.8 38.8 6.0 300.1
575 -3.2 -170.0 0.8 43.2 6.0 316.3
600 -3.5 -189.9 0.9 47.8 6.1 332.8
625 -3.7 -211.2 0.9 52.6 6.1 349.5
650 -3.9 -233.8 1.0 57.8 6.2 366.5
675 -4.2 -257.9 1.0 63.2 6.2 383.8
700 -4.4 -283.5 1.1 68.9 6.3 401.4
725 -4.7 -310.7 1.1 74.9 6.3 419.3
750 -4.9 -339.4 1.2 81.2 6.4 437.4
775 -5.2 -369.8 1.2 87.8 6.4 455.9
800 -5.5 -401.9 1.3 94.7 6.5 474.7

07/02/11 08:34, JBM/jbmucard-5.1.cgi

 

[Rob01]

Re: Not understanding something in JBM Ballistics

Mils and CM are not the same. Run both columns in mils. No need for CM to be there.

 

[BryanLitz]

Re: Not understanding something in JBM Ballistics

The MILS/meters relationship (10 cm/100 meters) only applies when the range is in meters. Your range is tabulated in yards.

-Bryan

 

[shane45]

Re: Not understanding something in JBM Ballistics

Understood. OK that looks a lot better. Missed the yd/m drop down. Thank you!

Trajectory &#956;Card
Range Drop Wind Lead
(m) (mil) (Clicks) (mil) (Clicks) (mil) (Clicks)
100 -0.0 -0.0 0.0 0.0 5.2 52.1
200 -0.5 -5.2 0.2 1.7 5.4 53.8
300 -1.2 -12.3 0.4 3.5 5.6 55.6
350 -1.6 -16.3 0.4 4.5 5.7 56.6
400 -2.0 -20.5 0.5 5.5 5.8 57.5
450 -2.5 -24.9 0.6 6.5 5.9 58.6
500 -3.0 -29.6 0.8 7.5 6.0 59.6
525 -3.2 -32.0 0.8 8.1 6.0 60.1
550 -3.5 -34.5 0.9 8.6 6.1 60.7
575 -3.7 -37.1 0.9 9.1 6.1 61.2
600 -4.0 -39.7 1.0 9.7 6.2 61.8
625 -4.2 -42.4 1.0 10.3 6.2 62.4
650 -4.5 -45.2 1.1 10.9 6.3 62.9
675 -4.8 -48.0 1.1 11.4 6.4 63.5
700 -5.1 -50.9 1.2 12.0 6.4 64.1
725 -5.4 -53.9 1.3 12.6 6.5 64.7
750 -5.7 -57.0 1.3 13.3 6.5 65.3
775 -6.0 -60.1 1.4 13.9 6.6 66.0
800 -6.3 -63.4 1.5 14.5 6.7 66.6

07/02/11 10:35, JBM/jbmucard-5.1.cgi

 

[Rob01]

Re: Not understanding something in JBM Ballistics

Get rid of clicks now and you will be set. Think in mils. Not clicks.

 

[shane45]

Re: Not understanding something in JBM Ballistics

But wait, confusion creeps in again. My scope is a S&B PMII mil/mil. In example one, its saying 29.1 cm for 300 yds which would be 29.1 clicks on my scope. Example 2 , even though corrected in meters is saying 12.3 clicks.

 

[shane45]

Re: Not understanding something in JBM Ballistics

Or mils even. I dont usualy think in clicks, I just dial in on the knobs. But trying to understand the underlying correlation and why they seem to not match up even remotely. I know I must be overlooking something fundamental.

 

[Lindy]

Re: Not understanding something in JBM Ballistics

Take Rob's advice - get rid of clicks. Get the output - and think - only in milliradians. Do it now, and rerun the table.

 

[jps2]

Re: Not understanding something in JBM Ballistics

As Rob01 said : forget the clicks.

when your drop chart says 3.2Mil, rotate your turret to 3 and 2 hashes; The turret is in 0.1Mil, the numbers are Mils so 3 mils and 2 more clicks

 

[shane45]

Re: Not understanding something in JBM Ballistics

I think its returning "clicks" because I put in .1 mil as the value to match up with my turrets. Im assuming it doesnt match perfectly because of a roundup somewhere in the math?

 

[Notso]

Re: Not understanding something in JBM Ballistics

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: shane45</div><div class="ubbcode-body">I think its returning "clicks" because I put in .1 mil as the value to match up with my turrets. Im assuming it doesnt match perfectly because of a roundup somewhere in the math? </div></div>
Don't put in .1 mil values. Use a whole number mil for the output and it will give you the correct values. IOW, Put in 1.0 Mil for both drop and windage units in the output field.

 

[mouse07410]

Re: Not understanding something in JBM Ballistics

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Notso</div><div class="ubbcode-body">Don't put in .1 mil values. Use a whole number mil for the output and it will give you the correct values. IOW, Put in 1.0 Mil for both drop and windage units in the output field. </div></div>
I find it convenient to have the 1st column for drop and windage in inches (or cm), and the 2nd one - in mil (1.0 value).

 

[shane45]

Re: Not understanding something in JBM Ballistics

Thanks for the assist guys!