The Forest service study was a good study in 1983 as I mentioned above, but who would exclude the update Garrett Hammerhead 540 gr for the 45-70 today?
Quote:
RECOMMENDED FOR USE ONLY IN MARLIN RIFLES BUILT SINCE 1998
Energy: 2880 ft/lbs: Taylor Knockout Value: 55; Meplat: .360”;
Chamber Pressure: 35,000-cup; Brinnell Hardness: 25;
Trajectory: +2” @ 50-yds, ZERO @ 120-YDS, -8.5@ 175-YDS
*All ballistic specs result from 22” barrels.
FIRST CHOICE for defense against heavy grizzly
Our 540-gr +P Hammerhead Ammo is the ideal choice for stopping heavy bears at close quarters or hunting them at short range. This Hammerhead bullet has a meplat (frontal flat) diameter of .360”, which is just one tenth of an inch less than bore diameter. With its tremendous weight to diameter ratio (sectional density) it provides end to end penetration on the heaviest of bears, with exit, and does tremendous damage per unit of penetration due to its extremely blunt front end. This load is carried exclusively by NOAA for protection against coastal grizzly attack. It is also carried by the National Marine Fisheries Service and the U.S. Geological Survey for protection from grizzly attack. For the specific task of stopping a grizzly charge, this ammo has no peer.
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http://www.garrettcartridges.com/4570540tech.html
In addition to increased muzzle velocity/energy bullets have likewise gone through an incredible evolution. The hardcast bullets such as the Hammerheads above hold together better than the old lead only bullets giving maximum penetration.
The only thing that you can really do with the 1983 study is the take home message of high penetration and using the biggest rifle you can comfortably shoot well. Fortunately, today, we have a lot of options for folks to choose from as jgcoastie listed. (hey, throw in the .444 to your list as well
Lots of ways to skin a cat.)