Setting up range/data cards?

[BigPineyTradingPost]

How do you figure out data cards with DA increments with whatever ballistic calculator?
Is it temperature related?
I hope this makes sense.

 

[Lowlight]

I would use Coldbore but you can go to JBM

Halfway down is the range card feature

JBM - Calculations

www.jbmballistics.com

 

[Spblademaker]

@lowlight Will the Weaponized Math app have a range card function too?

 

[Conrad101st]

I make a data card for where I hunt most, either the local area for deer or the mountains for elk. I use best guess for altitude and temperatures. Plug it into your StrelokPro and you can export to an excel table. Then I plug that table into my fat data card and laminate it.

 

[Lowlight]

@lowlight Will the Weaponized Math app have a range card function too?

A basic one you can technically make multiple versions based on DA

It’s pretty light in terms of horsepower because it wasn’t necessary, but that will keep it free

 

[Jack Master]

Below is the dope chart that I use for different density altitudes.

When filling this out I change my station pressure only to change DA. I tried to keep the same temperature at each DA. When I got down to 0 DA hornady 4dof was not giving me a result I thought was correct so I had to change the temp.

1. Use 59 or 60 degrees if you can. This is the standard temperature to measure station pressure.
2. Look up an altitude adjustment chart for different station pressures and use this to choose pressures to enter into your program that are in the increment you want. I used 2000 DA for each chart. (Or use an inline program. Google DA calculator)

Right chart of this used to find change in station pressure for wanted DA

 

[Jack Master]

How do you have a paper chart for Density Altitude (DA) changes in your dope? Do any of you have a DA sheet in your Data Book?

I have read and been told to have drop charts for every 2000DA change. My home range is usually around 2000DA. This means I need a drop chart for -2000ft, 0ft, 2000ft, 4000ft, 6000ft, 8000ft, 10,000ft. That's 7 pages in a dope book for one rifle. I don't really want to have that many pages for one rifle (yes, I want ONE data Book for all my rifles). With 3 rifles is 21 pages to sift through. So... below is the chart I made for changing DA. Now I have 2 pages, my Home range dope chart with the wind information on the back and a DA dope chart.

Things to Note

1. Data recorded - at the top of the chart is how I got the DA numbers. This way I can reference how temperature might change the DA as well as the station pressure. (note the comment in the margin about how temp change = DA change)
2. All of these are at 50% humidity. To keep this simple I had to eliminate a variable, humidity was it. While I think it will effect things more after 1000yds I don't think it has enough variance inside 1000 to worry about.
3. Wind - The wind row has 2 numbers in it. The 2 numbers are the wind speeds that are equivalent to the wind hold for 2000DA. Example - if I'm shooting at 6000DA, 800 yards - a 7mph hold is 0.9 mils (6mph from 2000DA) and a 12mph hold is 1.6mil (10mph hold for 2000DA) this allowed the chart to re-use 2 columns of information for each DA change and for me to know what my Rifle MPH is at each DA.
4. After doing this I think the chart will work out to 1000 or 1100 yards. After that a more refined DA chart may be warranted. At 1100 yards jumping 2000DA is a 0.4 mil jump, that's about 16" of change. For an accurate shot I recommend consulting your Ballistic program on the longer shots with changing DA, but these values will at least give you a starting point if you don't have any other information. of you'll need to pin down your true DA and guess between numbers if needed.
5. I presented this chart in 2 ways. 1st - straight data. 2nd is the plus or minus from the home range value. Doing the 2nd version can help us understand how much DA can really effect our dope. The 2nd if more for informational used and not necessarily something I would have in my data book.

Let me know what you think.

1st chart Raw DA values
View attachment 7172626

2nd chart - Difference in DA from my home range.
View attachment 7172627

Have a look at this post I did to explaine the chart

 

[Jack Master]

The last option would be to use 60 degrees, 29.92 barametric pressure and change your elevation in 2000 feet incriments or what ever increment you want. This method is not perfect but will be very close.