Ballistic Coefficient

[S.T.]

Hi everyone,

We are trying to find the ballistic coefficient for our bullets.

We are shooting sierra matchking htbp 168gr with 43gr varget powder.

What we could find on sierra website and in our lymann handloading book are different

On sierra website they say: .462 @ 2600 fps and above
.447 between 2600 and 2100 fps
.424 between 2100 and 1600 fps
.405 @ 1600 fps and below

In the Lymann book they say .462 @ 2491 fps.

What would be the best way for us to find the BC for our bullets?

Thanks

 

[snooker]

As you can see, BC varies as to velocity. Some ballistics programs will allow you to input your data and give you a theoritical number. The numbers you list are so close, I don't think you would see any difference.......its just a number.......that changes.

 

[nw mb]

...go with the sierra data on sierra bullets

...do you have a chronograph?

...i use BC as a comparison between bullets

...use a good ballistics calculator available for free on the internet...i use http://www.jbmballistics.com/ballistics/calculators/calculators.shtml...just because i like it...competition shooters may be able to tell you more

what interests you about BC?

all the best

 

[S.T.]

thanks snooker

 

[S.T.]

We are looking forward to shoot longer ranges and for our ballastic charts we need know the muzzle velocity and BC.

I do not have a chronograph yet but I'll probably buy one by the end of the week

Thanks

 

[mad max78]

Are these 308 cal? Bryan Litz has them listed in his book at a avg G7 of .218 and a avg G1 at .427

 

[S.T.]

Yes it is 308

Sorry i forgot to include this information