Why two chronographs

[bcoving]

Why do you need two chronographs if you want to measure velocity at different ranges for your software? Could'nt you just use one then move it further out? What's the advantage of two?

 

[kiwi3006]

First off I have never tried to calculate BC from chrono data.
I think the reason people want to use two is so that you can see the exact velocity loss for that one projectile.
If you only use one chrono then you would need to have a load that gave minimal ES and fire a resonable number of rounds (10 or more?) to get an average.
My gut feeling is that the velocity loss from several projectiles will be different so you will need to average them anyway, but you would probably need to fire less rounds.

Stu.

 

[Michael Eichele]

It just simply isnt accurate enough to get an average and then move the chrony further out. You really NEED to know the actual starting velocity and the ending velocity of any given shot for the best results. I have tried both methods and hands down, the double chrony method works the better of the 2.

 

[LewisH]

Old Chinese saying:

"Man with one clock always know what time it is.
Man with two clocks never know what time it is."

Maybe this wisdom also applies to chronographs?

 

[Michael Eichele]

Old Chinese saying:

"Man with one clock always know what time it is.
Man with two clocks never know what time it is."

Maybe this wisdom also applies to chronographs?

For muzzle velocity purposes only, you may be right.

For the purposes of testing a ballistic coeffiecient, the only way to beat 2 chronies may be the ohler acoustic set up and definatley doppler radar. Other than that, a cheap, easy way to get you a number to get started at LR is to shoot through double chronies.

 

[jmason]

M.E. is right!If you want to get serious and get your info as precise as affordable it's the only way to go.