Greetings everyone,
I'm trying to generate some ballistic tables for subsonic 22LR and have ran into a somewhat interesting issue.
As we all know, DA is a function of Temperature, Humidity and Atmospheric Pressure.
Strelok, in DA mode, will accept a DA value AND a temperature value. If I set DA=5000 and vary temperature, my ballistic solution changes
even though i've turned off powder temperature consideration/sensitivity and have one defined MV.
Since DA is not changing, I'm a bit lost as to why the trajectory of the bullet is changing when I change the temperature holding DA constant.
My guess is that Strelok's solver is using the required temperature input for mach # evaluations where speed of sound is required and a function of temperature.
I understand DA has temperature built into it but the software would not be able to back solve for it because technically you can have various different temperature values for the same DA, thus the need for the input.
If I take a normal bullet like 6.5 creed, and repeat the same exercise, the trajectory does NOT change when I vary temperature.
I guess my question is, is this phenomenon fundamentally true for rounds where the MV is basically hugging the subsonic range of values or is it only a bi-product of the software I happen to be using and the way it does the math under the hood?
My guess is, the bullet feels DA and only DA when it leaves that barrel and with the exception of ammo temp which I've eliminated as a variable here, the trajectory should not be affected if DA is held constant. Now when the bullet reaches transonic/subsonic regions, there must a temperature associated for that point....
It may be best to stick to temperature and station pressure for 22lr tables.
I'm trying to generate some ballistic tables for subsonic 22LR and have ran into a somewhat interesting issue.
As we all know, DA is a function of Temperature, Humidity and Atmospheric Pressure.
Strelok, in DA mode, will accept a DA value AND a temperature value. If I set DA=5000 and vary temperature, my ballistic solution changes
even though i've turned off powder temperature consideration/sensitivity and have one defined MV.
Since DA is not changing, I'm a bit lost as to why the trajectory of the bullet is changing when I change the temperature holding DA constant.
My guess is that Strelok's solver is using the required temperature input for mach # evaluations where speed of sound is required and a function of temperature.
I understand DA has temperature built into it but the software would not be able to back solve for it because technically you can have various different temperature values for the same DA, thus the need for the input.
If I take a normal bullet like 6.5 creed, and repeat the same exercise, the trajectory does NOT change when I vary temperature.
I guess my question is, is this phenomenon fundamentally true for rounds where the MV is basically hugging the subsonic range of values or is it only a bi-product of the software I happen to be using and the way it does the math under the hood?
My guess is, the bullet feels DA and only DA when it leaves that barrel and with the exception of ammo temp which I've eliminated as a variable here, the trajectory should not be affected if DA is held constant. Now when the bullet reaches transonic/subsonic regions, there must a temperature associated for that point....
It may be best to stick to temperature and station pressure for 22lr tables.
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