Thread: Cast bullet bc’s

Anyone know how to calculate the bc of a bullet
Just trying to work out the bc of a couple of bullets I use for bpcr long range

Drag Function form

Have fun.

Weight estimates seem to be bang on and from the few bullets I have checked, the estimated BCs seem to be reasonably close as well. It's an interesting tool to play around with and works for VLDs just as well as flat nose. Only thing I haven't been able to reproduce is elliptical nose projectiles.

Originally Posted by rambo-6mmrem

Anyone know how to calculate the bc of a bullet
Just trying to work out the bc of a couple of bullets I use for bpcr long range

Can a Labradar give the data to calculate BCs ?

wikipedia has a series of formulars

Zero at 100

Shoot at 400 target

Measure drop in inches or moa

Use ballistic calculator and keep adding bc value until calculator shows actual measured drop

That will get you close

Originally Posted by 7mmsaum

Zero at 100

Shoot at 400 target

Measure drop in inches or moa

Use ballistic calculator and keep adding bc value until calculator shows actual measured drop

That will get you close

You would think so eh
I have known drops all the way out to 805yards
When I use one of them (I think I used my 590yard dope)
And mv is known also
I added bc until it matched that number as you say
Came back with a bc of 0.750 lol I find it very hard to believe that a 334gn.375 round nose bullet has a .75 bc lol unless I’ve found the holy grail of bullets lol
Plus when I used that bc and tryed my other known dopes none of them matched they weren’t far off 4 or 5 moa though

With cast bullets being mostly in the near transsonic range or subsonic in many cases what effect does that have on the bc. I know Lee publish bc values for their molds and I suspect other makers might as well.