There are many BC calculator programs out there. A Google search using 'ballistic coeffecient calculator' came up with many pages of information. Also www.snipercountry.com
has a good section on ballistics.
The Lyman Reloading Handbook
has some of the information you're looking for. I have an older edition (46th edition) and it lists only (numbers listed under Centerfire rifle cartridges and not under black powder guns BTW). Perhaps a newer edition has more numbers;
#457125 weight-464 Velocity Boundaries; upper1600 lower 1200 BC Values; high velocities .391 intermediate velocities .380 low velocities .380
#515141 weitht-422 Velocity Boundaries; upper1600 lower 1200 BC Values; high velocities .250 intermediate velocities .250 low velocities .225
There is/was a book put out by Pachmyr called Extended Ballistiics For The Advanced Rifleman
by Art Blatt
that has useful information in it. IIRC soem of the other reloading manuals have the BC information listed in the reloading pages.
Just remembered I also have the Lyman Cast Bulet Handbook
which is an even better source than the first Lyman book;
You may also try contacting Lyman direct. They can be found at www.pachmayr.com