best Ballistic Coefficient calculator

[pouriya]

Hello guys
i looking for an app that can calculate my BC by giving it my velocity in different distances!
do you have any suggestion?
i used to applied ballistic app on android but it can't calculate BC.

 

[Delfuego]

Most if not all apps only adjust velocity by plugging in Distance=Drop. Shooter App will allow you to create "Banded BC" like Sierra uses. You can tell the calculator what the BC is at different velocities to adjust your drop curve.

 

[GSPV]

I believe that you are on the right track. Using Doppler radar to get downrange velocities is how the big boys do it.

I don’t know of a calculator that lets you do it directly.

I do know that you could use any of the trajectory calculators to back into the BC from your observed velocities and drops.

 

[pouriya]

i have found some other website that gives the BC online but i don't want it to be online and its better to be on an app for me! i don't know applied ballistic cannot calculate it!

 

[Bigdad123]

How are you going to confirm your velocities at various ranges? Do you have access to a high end dopler unit or will you use a chronograph placed at each range and fire a series of shots over it?

 

[pouriya]

How are you going to confirm your velocities at various ranges? Do you have access to a high end dopler unit or will you use a chronograph placed at each range and fire a series of shots over it?

i use to labradar to detect the velocity on different ranges!

 

[watercam]

JBM Ballistics has been extremely close for me. Always in the black with their solutions out to 1K yards.

 

[mensajd]

Labradar gives you v up to around 100 yds. Since you have an extrapolated v0 (+-small error term), use v0 and then tweak BC in your ballistic app until the calculated data best fits your measured velocity at distance data (taking into account corresponding atmospheric/weather/elevation data). Haven't done sensitivity analysis on this method so I don't know if extrapolated data at longer ranges will be useful, but it's trivial to test empirically.

 

[pouriya]

JBM Ballistics has been extremely close for me. Always in the black with their solutions out to 1K yards.

JBM has only online!i want to use it offline,its very accurate i checked!

 

[pouriya]

Labradar gives you v up to around 100 yds. Since you have an extrapolated v0 (+-small error term), use v0 and then tweak BC in your ballistic app until the calculated data best fits your measured velocity at distance data (taking into account corresponding atmospheric/weather/elevation data). Haven't done sensitivity analysis on this method so I don't know if extrapolated data at longer ranges will be useful, but it's trivial to test empirically.

the BC of companies is a little different from the one you calculate yourself!it's better to calculate yourself because of accuracy.

 

[Bart B.]

I've chronographed then shot several 30 caliber Sierra HPMKs at 100 yards for sight zeros, then lowered sight elevation to match bulled drop plus sight height.

Then used Sierra's software to calculate zeros at 600 through 1000 yards; atmospheric conditions adjusted for. Zeros at those ranges were within a half MOA of calculated values.

This is using aperture sights whose click values can be calculated to several decimal places. Sight radius can be measured to .01" tolerance. At 36 inches, that's a tiny error.

 

[CharlieNC]

You can manually increment the bc value to find the one which best predicts the measured results. That is what I do using velocity to fit trajectories at numerous distances, vs one yardage truing function in the app.

 

[DaveTooley]

i use to labradar to detect the velocity on different ranges!

Multiple units I assume?

 

[Depart123]

Hello guys
i looking for an app that can calculate my BC by giving it my velocity in different distances!
do you have any suggestion?
i used to applied ballistic app on android but it can't calculate BC.

Strelok Pro has a multi BC function. True the velocity with the published BC at 500 yards, then adjust subsequent BC's to match down range drops.

 

[spife7980]

Multiple units I assume?

The labradar should be able to radar the bullet from muzzle to 100 yards out. His phrasing was confusing.

 

[STOMP442]

Why reinvent the wheel? Litz and the gang have already done the ballistic testing and have their tested ballistic values in the app already. I have found the app to be very accurate to the point where I see no value in going through the effort and spending the time calculating my own. With correct inputs, I have had no issues using the applied ballistics app to achieve first round hits out to 1000 with ease.

 

[Delfuego]

Why reinvent the wheel? Litz and the gang have already done the ballistic testing and have their tested ballistic values in the app already. I have found the app to be very accurate to the point where I see no value in going through the effort and spending the time calculating my own. With correct inputs, I have had no issues using the applied ballistics app to achieve first round hits out to 1000 with ease.

Is that so? With ease?

Damn near every calculator will get you to 1k without issue. Why is it that I had to adjust my BC .020+/- on a Berger 180 Hybrid to get it anywhere near what AB was telling me. If you want to drink the Koolaide please enjoy it, but there are reasons for adjusting the BC. I actually thought AB would allow me to adjust BC to match actual drop, but it only allows you to adjust velocity to match your dope. If I tried to adjust velocity in AB to match what I was shooting at ELR ranges, the output turned to garbage. I even bought the "Custom Curve" for the bullet from AB, even worse data. The only thing that would work was manually adjusting BC to match my dope.

 

[STOMP442]

Is that so? With ease?

Damn near every calculator will get you to 1k without issue. Why is it that I had to adjust my BC .020+/- on a Berger 180 Hybrid to get it anywhere near what AB was telling me. If you want to drink the Koolaide please enjoy it, but there are reasons for adjusting the BC. I actually thought AB would allow me to adjust BC to match actual drop, but it only allows you to adjust velocity to match your dope. If I tried to adjust velocity in AB to match what I was shooting at ELR ranges, the output turned to garbage. I even bought the "Custom Curve" for the bullet from AB, even worse data. The only thing that would work was manually adjusting BC to match my dope.

Yes with ease. Garbage in garbage out. I am willing to bet you have some other setting you are missing when setting up your app. Are you positive your scope is moving the proper amount it states or are you assuming 1/4" per click like the turret says? Is your scope height correct? Are you certain of your zero? Have you messed with elevation correction factors? there are lots of little things you can adjust besides BC that can have a big effect on your trajectory calculations.

 

[Delfuego]

I got a top 10 finish at the ELR match in Wyoming last week so I think I'm good.

 

[mensajd]

Why reinvent the wheel? Litz and the gang have already done the ballistic testing and have their tested ballistic values in the app already. I have found the app to be very accurate to the point where I see no value in going through the effort and spending the time calculating my own. With correct inputs, I have had no issues using the applied ballistics app to achieve first round hits out to 1000 with ease.

Wow, proof by eminent authority? MIT teaches that the method is no proof at all.

1. Proof by reference to eminent authority: “I saw Fermat in the elevator and he said he had a proof . . .”

I'll take reliable empirical data every time - though I majored in theoretical math, I concur with the view that facts are stubborn things.