Guys, this is an incredible wealth of information. Thanks. I hope the thread continues awhile, and I hope others are enjoying the exchange as much as I am.
* * * If I'm getting the gist of this discussion, it seems like the 240 grain soft point I've killed deer with was always moving around 1200-1500 fps - either 25 yards straight out of a .44 Mag revolver, 50 yards with a 12 gauge saboted setup, 75 yards with a .50 muzzleloading saboted setup, or 100 yards straignt out of a lever action .44 Magnum. All worked GREAT.
If I took that same bullet and shot it in a .444 Marlin or a .429 Whizbang, and it was going 2500 fps - it might be going so fast it would not perform well, or at least not perform the 'drill a hole clear through the deer' way the others have. It WOULD transfer lots of energy, providing it fragmented IN the deer, and would kill the deer humanely, IF it didn't hit bone and perhaps detonate so soon it didn't reach vitals. ALSO I'd have more meat destroyed than the 'drill through' method I get with slower velocities.
Now if I limited my shooting of the Whizbang to 300 yards, and the bullet was slowed down to 1500 fps THERE, then I'd get the same performance I now get at close range, provided I can hit the target at that range taking into account trajectory, wind drift, and time of flight vs. the deer bolting. If I was waiting for that 300 yard deer, and a 30 yard deer came into view, however, I'd be better off pulling out my Super Blackhawk and shooting that same bullet more slowly, unless I had some really 'light' loads for the Whizbang which gave me my 1500 fps at 30 yards rather than at 300 yards.
Finally, the 180gr bullets we assume (perhaps not always correctly) to be more fragile, since they are usually assumed to be used for 2-leg varmints at 20 feet ranges. Still, if you had a solid 180 grain which was 'tough' you'd face two hurdles - one being the lesser ballistic coefficient vs. the longer bullets, which might result in a more curved trajectory which would negate the velocity advantage in terms of aiming. The other being the lesser sectional density, so even if the projectile were tough enough to 'drill through,' it might NOT do so as well.
Now if you had a 180 gr. bullet proportional to that 240 grain .429 one, say .40 caliber or whatever, so the sectional density WAS the same, you'd drill the hole just about as successfully, only it would be a smaller hole, and if the hole is too small, you get less shock, slower death, and if you do have to trail an animal, less blood to follow.
If the preceding re-statement of much of what was posted is halfway correct, then THAT explains why all you guys really like your .45 caliber guns, and if you use your .44's or .35's you want heavy bullets even though the velocity is lower vs. the available lighter ones. (...and I always thought the advantage of the smaller diameter bullets was only the fact that they went faster and flatter!)
None of this negates the ultra long-range advantage of the 7mm Mag if you're in the mountains, or the flat-shooting advantage of a .22 centerfire for prarie dogs, but it does explain why for medium and large game under 300 yards you guys generally seem to prefer large heavy bullets at moderate velocities.
Now (maybe another thread?) ...with these moderate velocities, how often do you really need gas checks, then...?
(...see all you guys who gripe about 'OT' posts, we really CAN do lots of stuff on guns.
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Sorry if the 'old timers' may find this and similar topics repeats of discussions which undoubtedly take place every few months or couple of years, but to myself and other relative newbies, there is lots to learn so I for one like to ask lots of dumb questions...
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