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Bullet Penetration...Weight or Energy???
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I just purchased a .460 S&W with a 2.75" barrel for a bear gun. I'm wondering if I'm better off with a lighter bullet which has higher energy, or a heavier bullet with less energy (please keep in mind that this is for Grizzly Bears). Given the choices below, which bullet would you choose (all Corbons). Please also consider bullet type:
200 gr with 2350 ft lbs energy (XPB, Barnes Pistol Bullet)
275 gr with 2034 ft lbs energy ("""""")
325 gr with 1965 ft lbs energy (Bonded Core)
395 gr with 2040 ft lbs energy (HC, Hard Cast)
Thank you!
This is a duplicate post, posted in different forums for more exposure.
200 gr with 2350 ft lbs energy (XPB, Barnes Pistol Bullet)
275 gr with 2034 ft lbs energy ("""""")
325 gr with 1965 ft lbs energy (Bonded Core)
395 gr with 2040 ft lbs energy (HC, Hard Cast)
Thank you!
This is a duplicate post, posted in different forums for more exposure.
Comments
I would go with MASS to break bone and get deep into a bear. A 12 ga with slugs is easier on your * when fired. [:D]
...I thought that's what I bought, only with a 2" barrel...[^][:o)][:D]
http://www.handloads.com/calc/quick.asp
I'd say that bigazz 395gr hardcast will put a whallop on anything.
For the chart above, I entered the given information and changed the variable (in this case velocity) to get the energy number to match. Assuming there are no miscalculations or typo's, the velocity I used to compare these are as follows....
200gr XPB @ 2301 fps to give 2350 ft lbs
275gr XPB @ 1826 fps gives 2034 ft lbs
325gr BC @ 1650 fps
395gr HC @ 1525 fps
From the chart they calculate energy, momentum, and the Taylor KO number. Whether you trust that number or not is up to you. It's been developed by African Hunter John Taylor and is supposed to give a good number to compare as far as "killing power".
The Momentum and KO numbers are as follows....
Weight..Bullet type.....Momentum.....KO
200gr XPB...................65........30
275gr XPB...................71........31
325gr BC....................76........35
395gr HC....................86........39
Obiviously the bullet choice plays a part as well, but that 395 cast would stop anything on this continent. I compared the 395gr HC bullet to a 375H&H Mag firing 300gr slugs at 2470fps. The KO #'s are the same.
FWIW, I guess.
defensive shooting of bears with the revolver
by Randy Garrett
Single-action vs Double-action
I like both single-action and double-action revolvers for hunting, however when carried for self-defense from bear attack, there is a pretty strong consensus that the double-action revolver is the better choice. Since bear attacks invariably occur with incredible speed, there is a very considerable possibility that the attacking bear will reach the shooter before he has had an opportunity to effectively deploy his sidearm. If that does occur, it is generally believed that a double-action revolver offers the shooter a better chance of prevailing since it can be fired by simply pulling the trigger. The necessity of thumbing the hammer on a single-action revolver presents a substantial mechanical obstacle when the shooter is placed in such demanding circumstances, as the throttling provided by a bear attack is vigorous in the extreme.
Caliber selection
Since the only completely reliable shot placement against an attacking bear is one that destroys essential parts of the central nervous system, it could be argued that any caliber/load combination capable of shooting through the skull of a big bruin is a reasonable choice. However, the larger the caliber the greater the potential for disabling an attacking bear with a less than perfect shot. Therefore, the best choice is likely to be the biggest caliber the shooter can handle in a desperate struggle where all shooting will be done one-handed. In my opinion, this would include calibers as small as the 41 Magnum, assuming proper bullet selection.
Bullet selection
Where defense against bear attack is concerned, the best bullets for the large caliber handgun are clearly proper hard-cast bullets. Expanding bullets are far too likely to fracture when impacted into the tough bone of a bear's skull. This should be rather obvious as any bullet designed to expand against the light resistance of a deer's rib cage cannot be depended upon for major bone busting on a big bear. When selecting a hard-cast bullet for such applications, one should be careful to choose an extremely heavy bullet with a broad frontal flat (meplat). It is also important that the casting possess substantial inherent strength, with a hardness rating of at least 19-Brinnell. The importance of selecting a heavy bullet is twofold. First, heavier bullets penetrate deeper than lighter bullets. Second, since heavier bullets cannot be driven as fast as lighter bullets, they experience less impact stress and are therefore less likely to fracture upon impact. This is very important, as the amount of stress experienced by a bullet upon impact is the result of the speed of impact and the toughness of the target. When the target is close and extremely tough, reliable performance is always best achieved by increasing bullet weight and decreasing velocity. The importance of selecting a bullet with a broad meplat is also critical, as broad meplated bullets tend to penetrate deeper than small meplated bullets. It has become obvious to me through the years that although logic would seem to suggest that heavy bullets with small meplats should penetrate deeper than blunter bullets of the same weight and velocity, they usually don't. This is quite interesting, as it would seem that the bullet with the smaller meplat would offer less resistance to penetration and therefore should penetrate better than the blunter bullet. However, nearly three decades of penetration testing with the 44 Magnum has established beyond any doubt that the blunter designs penetrate the best. The truncated cone is an excellent example of this. Although possessing meplats in the .210-inch to .230-inch range, truncated cones do not penetrate as deeply as semi-wadcutters of the same weight and impact velocity, and yet the semi-wadcutters I have tested possess meplat diameters of about .285-inch. Later testing revealed that penetration would continue to increase as the meplats increased in diameter up to about .320-inch. However, my penetration testing demonstrated that meplat diameters significantly greater than .320-inch, in 44 caliber, did not increase penetration depth, but instead led to decreased penetration depth. It is always easier to observe than explain, however it is my opinion that the reason for this pertains to the disparity in weight distribution of small meplated bullets. Simply stated, when the back half of the bullet carries significantly more weight than the front half, the back half tends to over-take the front half upon impact. In other words, the bullet tends to go sideways since the back half carries more weight and has more inertia. As the weight disparity between the two ends of the bullet is reduced, as in blunter designs, there is clearly less of a tendency for the back half to over-take the front half, and the bullet takes a straighter and deeper path. However, once this weight disparity has been corrected, any further increases in meplat diameter tend to decrease penetration depth as terminal stability can no longer be improved.
Final thoughts
It should be clearly understood that although a properly loaded large caliber handgun can be successfully deployed against an attacking bear, it certainly is not the gun of choice. It is best regarded as the gun of last resort. In my opinion, the short barreled lever-action carbine firing heavy bullets at modest speed reins supreme for the specific task of stopping a determined bruin. Also, as with the handgun, the lever-action carbine should be chambered in the largest caliber the shooter can handle. For most shooters this is probably the 45-70 with blunt hard-cast bullets of extreme weight.