Anyone have a clue as to how to determine the BC of large cast slugs that likely aren't listed in anyone's ballistic tables? Specifically, I would like to get a BC and trajectory information on a couple of .72 cast bullets, one an 835-grain "Cotton spool" paradox-style bullet, and the other an 1100-grain flatpoint that looks like an LBT style bullet writ large. I know I could shoot them over the chrony at the muzzle and at 50 yards or 100 yards and work backward, but in this case, I don't have the rifle ( a Kodiak double) and am trying to determine if these would be suitably effective out to 135 yards or so for my hunting purposes before buying the rifle.

First, try this one as an easy-to-use "good estimator" program.

http://www.handloads.com/calc/

It does a pretty good job of giving you what you are after without burying you in details.

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If you like lots of diagrams and details, this one may be better for you.

http://www.uslink.net/~tom1/calcbc/calcbc.htm

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Bill, good luck on the big bullet.

Oldfeller

Calculate the sectional density of the slug, there's various sites on the net to accomplish this. Then use the SD and find a nose shape similar in another caliber with the same SD-- and your then very close to the BC.