I like both single actions and double action revolvers for hunting, but I don't think one is inherently faster to get into action for the first shot. Ed McGivern set all kinds of speed records with S&W double actions. However, most of the guys that advocate double actions for bear defense do so because, as the arguement goes, if a bear gets you down which he may well do if he attacks, the mechanical requirements of firing a double action gun are significantly less difficult since one must only keep pulling the trigger, as opposed to having to thumb the hammer.
Regarding the penetration of FMJs compared to good cast bullets, it depends upon the specific bullets considered. However, about 28-yrs ago before I started casting bullets I discovered that the Sierra 250-gr FMJ silhouette bullet was an excellent bullet for penetration, whereas some others that did not have a flat on the front, or as big a flat, were not. At the velocities produced by that early Sierra, deformation was not a problem. It has become apparent to me through the years that although logic would seem to suggest that a bullet with less frontal area should out-penetrate a bullet with more frontal area, given the same weight and velocity and ability to resist deformation, it usually doesn't. The truncated cone is an excellent example. There are many extremely heavy truncated cone cast bullets available for the 44 Magnum, and they usually have a meplat diameter of between .210-inch and .230-inch. They look like they should penetrate until next week with all that weight behind the small front end (meplat), but in fact they produce less penetration than SWCs of the same weight driven to the same speed. Yet the SWCs are blunter. As I then tried castings with meplats with diameters in the .320-inch class I found that they tended to out-penetrate the SWCs (same weight and velocity), and again they were blunter than the SWCs. This strongly suggested to me that there was more going on than just sectional density and resistance to penetration, as a result of the meplat diameter. Since it is easier to observe than explain, I can only speculate, but the testing I have done suggests to me that when the front half of the bullet weighs considerably less than the back half, the back half has a tendency to try to overtake the front half upon impact with a tough target (animal or penetration medium). This takes the form of the bullet yawing or going sideways which obviously greatly reduces penetration. Those bullets that carry as much or nearly as much weight on the front half of the bullet, tend to be much more stable in that regard and produce straighter and deeper penetration channels, and usually come to a stop nose first (at least in consistent penetration mediums, and apparently also in game). This is interesting, as one might normally conclude that the blunter bullet would have to lose the penetration contest, quite simply because it produces more resistance. However, the issue of terminal stability seems to outweight or overwhelm any advantage that small meplats would seem to offer with regards to pushing a smaller front end, which it would seem should produce less resistance. It appears that the rigors of impact are substantial enough for the bullet to lose virtually all of its aerodynamic stability and yaw or go sideways, again if a significant disparity exists between the weight of the front half and the back half of the bullet. However, when one tries a full caliber wadcutter of the same weight and velocity, one starts to observe a definite decrease in penetration depth. This would suggest that meplat diameter greater than that required to achieve terminal stability will reduce penetration depth, since no more terminal stability can be achieved. At this point, the bluntness catches up with the penetration ability of the bullet and no longer contributes to terminal stability.
Regarding the 45 Colt vs the 44 Magnum, it is my view that it is a very close call, but that the 45 Colt might well out-penetrate and slightly out-perform the 44 Magnum when taken to its full safe potential from a six shooter. However, the difference appears to be small. The 45 Colt as fired from a Ruger, for instance, is a great choice, at least in potential, and there is no good reason for the handloader to go to the 44 Magnum for maximum effectivenss if he already has a strong 45 Colt to work with.
For my use, and this is just personal, I carry the 44 Magnum with hard-cast bullets of great weight and meplat diameters of .320-inch. The gun I carry as a last resort defense revolver is my 5 and 1/2 inch Redhawk. It is relatively easy to get out of the holter (when compared to longer barrels), and it will carry a bigger load than any other six shooters out there due to strength and cylinder length (except for the Super Redhawk which is of equal strength and cylinder length dimensions). It is also double action, and as such seems to me to be more idiot proof when in a desperate life and death struggle like a mauling (heaven forbid).
[This message has been edited by Randy Garrett (edited December 08, 1999).]
[This message has been edited by Randy Garrett (edited December 08, 1999).]