Long Range Hunting Online Magazine Density Altitude w/a Ballistics Program
 Home LRH Store Forums Long Range Rifles Articles Reviews Video G7 Ballistics Calculator Rules & FAQ Register Search Today's Posts Mark Forums Read

# Density Altitude w/a Ballistics Program

#1
11-20-2013, 11:03 AM
 Bronze Member Join Date: Jun 2013 Posts: 87
Density Altitude w/a Ballistics Program

I have a Kestrel that I use to get my DA. I then put the DA into Ballistic AE which also asks me for the Temp or Mach.

Here's my question. DA is calculated as:
Pressure Altitude + [120 x (OAT - ISA Temp)]

OAT is local temperature from a thermometer.
ISA Temp is always 15 °C at sea level.

From that formula, it looks like DA includes temperature already. Why is Ballistic AE asking for Temp. again?
#2
11-20-2013, 01:51 PM
 Bronze Member Join Date: Jun 2013 Posts: 87
Re: Density Altitude w/a Ballistics Program

Quote:
 Originally Posted by bill123 I have a Kestrel that I use to get my DA. I then put the DA into Ballistic AE which also asks me for the Temp or Mach. Here's my question. DA is calculated as: Pressure Altitude + [120 x (OAT - ISA Temp)] OAT is local temperature from a thermometer. ISA Temp is always 15 °C at sea level. From that formula, it looks like DA includes temperature already. Why is Ballistic AE asking for Temp. again?
Got the answer myself. The Atmosphere pages ask for Temp to calculate Mach. DA already takes Temp. into account.
#3
11-20-2013, 02:04 PM
 Gold Member Join Date: Feb 2013 Location: Central MT Posts: 548
Re: Density Altitude w/a Ballistics Program

If your ballistics program is using temperature regression for correcting MV according to powder temperature you will need the temperature. Another consideration when using DA requiring a separate temperature input.
__________________
Shoot CONFIDENT, Shoot SMART, Shoot STRAIGHT
#4
11-20-2013, 02:13 PM
 Bronze Member Join Date: Jun 2013 Posts: 87
Re: Density Altitude w/a Ballistics Program

Quote:
 Originally Posted by MMERSS Additionally, If your ballistics program is using temperature regression for correcting MV according to powder temperature you will need the temperature. Another consideration when using DA requiring a separate temperature input.
Thanks, I'll look into that as well.

 Bookmarks

 Thread Tools Display Modes Linear Mode

 Current Poll Do you wear hearing protection while hunting? Usually do Usually do not No but I probably will in future
 Current Poll - 2 Do you have a high speed Internet connection? Yes, DSL, satellite, wireless or something else. - 89.73% No, only dialup right now. - 10.27% Total Votes: 3,251You may not vote on this poll.

All times are GMT -5. The time now is 06:51 AM.