Anyone have an estimate of the ballistic coefficient of the 405 gr Remington SN bullet for the .45/70?

I think it will be close enough to the cast bullet I make to allow me a to get a rough ballistic curve.

Thanks!

it usta be on remington's site somewhere. IIRC it was in the 0.180 - 0.210 range. just above "brick" but below "rock."

Sierra Infinity 5.1 indicates it uses a .281 BC for all velocity boundaries.

Ballistic Coefficients to Velocity Bounds.
0.281 for all velocity boundaries.

.458 dia. 45-70 Govt, 405 gr. SP

Lyman cast bullet #457193 (405 grain flat nosed)has a ballistic coefficient of .307 --S40

quote:

Originally posted by wrongtarget:
Sierra Infinity 5.1 indicates it uses a .281 BC for all velocity boundaries.

Ballistic Coefficients to Velocity Bounds.
0.281 for all velocity boundaries.

.458 dia. 45-70 Govt, 405 gr. SP

The Speer 400gr is pretty close in shape to the RCL. I would bet right around .220?

The tables that come with the QuickTARGET software list .280 as the BC.

One of the calculators on this site will estimate a BC for you based on bullet dimensions. Unfortunately, lead bullets usually have bands which the calculator doesn't consider. If you have a chronograph, one of the other calculators there will let you compute the apparent BC, which you can then use in the calculator for trajectory and wind drift.

well then I stand corrected; the 405 is a bit slicker than a rock after all: Rem 405 BC

it is 0.281