How can I determine ballistic coefficient for CBs?

[famdoc2892]

My ballistics program always asks for BC of projectiles to determine trajectory, drops, zero, maximum point-blank range, etc. That's great when j-words manufacturers publish them, not so much when I'm making them! Can I do this myself?

[Doc Highwall]

In Lymans cast bullet book they give some for their bullets.

[EdS]

My ballistics program always asks for BC of projectiles to determine trajectory, drops, zero, maximum point-blank range, etc. That's great when j-words manufacturers publish them, not so much when I'm making them! Can I do this myself?

BC is all about the bullet's shape. For a reasonable approximation, you can compare the shape of your cast boolit to that of j-word bullets. Pick one that's as similar as possible and use its BC in the calculation. The calculated trajectories are themselves approximations, and you can get pretty close. -Ed

[famdoc2892]

I use a lot of Sierra bullets for handloading, I'll check out their catalog.

[357maximum]

I have found that the best way to KNOW the drop is to move the bench farther from the sand pile. [smilie=2::Fire::mrgreen:

[Moonie]

I've used this to do a rough estimate:

http://tmtpages.com/calcbc/calcbc.htm