Online DA calc's vs Kestrel

[A&8's]

Has anyone compared your kestrel to any of the online DA cals, such as: http://www.pilotfriend.com/pilot_resources/density.htm

When I do, the DA isn't the same. The online calc is about 500 higher.

I'm using the inputs from my Kestrel of:

Elev - 416'
Air Temp - 74.4F
Press - 29.47"Hg
Dew pnt - 62.4

Online cal shows a DA of: 2271
Kestrel shows: 1700 +/-

 

[LawnMM]

The Kestrel is continually calculating the result based on live readings where you're standing.

The calculator online is giving you an answer based on what you plugged in.

Look at the altitude screen, it fluctuates a few hundred feet constantly based on changes the Kestrel picks up.

 

[Dthomas3523]

Also, ~500 won’t make much of a difference. .1 or less at 1k for most rifles

 

[spearknives]

Having a kestral with a ballistic calculator is very handy when your packing your gear around.

 

[A&8's]

The Kestrel is continually calculating the result based on live readings where you're standing.

The calculator online is giving you an answer based on what you plugged in.

Look at the altitude screen, it fluctuates a few hundred feet constantly based on changes the Kestrel picks up.

I understand the DA on the kestrel bounces slightly...slightly. But not 500'.

Also, the alt screen doesn't vary 1', providing the kestrel is stationary.

 

[A&8's]

Also, ~500 won’t make much of a difference. .1 or less at 1k for most rifles

I understand that +/-500' won't make a difference. That wasn't my question. (no disrespect intended)

 

[A&8's]

Having a kestral with a ballistic calculator is very handy when your packing your gear around.

Not sure where you was meaning with this. But, my intention was to make hard data cards for an upcoming trip 900 miles away. Not to mention 4000' different in elevation. So I didn't have to reply on elec cals.

 

[LawnMM]

I've never even heard of a 5700 going down but to each his own I guess

 

[_Windrider_]

Has anyone compared your kestrel to any of the online DA cals, such as: http://www.pilotfriend.com/pilot_resources/density.htm

When I do, the DA isn't the same. The online calc is about 500 higher.

I'm using the inputs from my Kestrel of:

Elev - 416'
Air Temp - 74.4F
Press - 29.47"Hg
Dew pnt - 62.4

Online cal shows a DA of: 2271
Kestrel shows: 1700 +/-

Double check the online calculator is looking for station pressure input. If you are using an aviation based calculator it likely is looking for corrected pressure which is why you are getting the error. Use this one

Density Altitude Calculator

www.weather.gov

Dead on

If u r interested I’ll tech you how to ballpark DA without a Calc.

 

[sleeplz]

I'm still at the stage where I'm wondering if a kestrel is that much better than strelok pro. Other than wind, which isn't being read at the bullets flight path, I'm not sure a kestrel is needed.

 

[A&8's]

I've never even heard of a 5700 going down but to each his own I guess

I guess that's one of the many differences between millennials and those of us raised writing stuff down with a pen.

 

[A&8's]

Double check the online calculator is looking for station pressure input. If you are using an aviation based calculator it likely is looking for corrected pressure which is why you are getting the error. Use this one

Density Altitude Calculator

www.weather.gov

Dead on

View attachment 7154410

If u r interested I’ll tech you how to ballpark DA without a Calc.

Sure. I'm all ears. PM me if you'd rather than post here. Either is fine with me.

 

[_Windrider_]

Sure. I'm all ears. PM me if you'd rather than post here. Either is fine with me.

DA changes about 1000 ft per 15 degrees F from standard temp. Using just standard lapse rates and temperatures you can get DA within 2-300 feet by just doing that.

Example:
Elevation 3000 ft
Temp 80 F

Standard temp at 3000 ft is (approx) 50 F

DA is approx 5000 ft

(80-50)/15 = 2.

Add 2000 to elevation to get 5000 DA

This is a ballpark because it does not account for the effects of pressure or humidity (humidity doesn’t matter much anyway)

Using your example above

Standard temp at 400ft is call it 58F.

74-58 = 16

16/15 = 1 for simplicity.

400 + 1000 = 1400. That’s pretty close.

 

[Dthomas3523]

I'm still at the stage where I'm wondering if a kestrel is that much better than strelok pro. Other than wind, which isn't being read at the bullets flight path, I'm not sure a kestrel is needed.

Depends on what/where you shoot and what’s important to you.

For me, I don’t like having to deal with my phone touch screen. When it’s 110 outside and I’m soaking wet from sweat, I have to keep wiping the screen to use it. Also phones can overheat pretty quick and go into standby mode until they cool.

Same thing when it’s raining. The touch screen isn’t that reliable without being frustrating.

Kestrel is also easier for me to manipulate with one hand at all times.

And one of the biggest benefits, without my phone around I’m not dicking around on here or with email instead of focusing on shooting.

If none of that matters to you or you’re doing most of your shooting in fair/moderate weather, then the kestrel isn’t as appealing IMO.

 

[_Windrider_]

Depends on what/where you shoot and what’s important to you.

For me, I don’t like having to deal with my phone touch screen. When it’s 110 outside and I’m soaking wet from sweat, I have to keep wiping the screen to use it. Also phones can overheat pretty quick and go into standby mode until they cool.

Same thing when it’s raining. The touch screen isn’t that reliable without being frustrating.

Kestrel is also easier for me to manipulate with one hand at all times.

And one of the biggest benefits, without my phone around I’m not dicking around on here or with email instead of focusing on shooting.

If none of that matters to you or you’re doing most of your shooting in fair/moderate weather, then the kestrel isn’t as appealing IMO.

I agree. Touchscreen is a pain in the ass.

 

[LawnMM]

I guess that's one of the many differences between millennials and those of us raised writing stuff down with a pen.

It's more like the difference between Grandpa who refuses to use email so he writes letters that take ten days to arrive via snail mail instead of trying something new.