Bullet Enery and velocity

[Greg Duerr]

I read something that said that a bullet needs so much velocity and energy when it gets to the intended target to make a clean kill......................

Im thinking that for Deer the bullet should be traveling at 1500fps with an energy level of 1000 foot lbs......................is this correct??

The reason I ask is that I was told that a .243 AI shooting a 105 berger at 3200 is only effective out to 400 yds.................but when doing a ballistic calculation that combination has a lot more at 400 yards than is needed................

So whats the real answer?

 

[BlackStreak]

I picture energy vs size of game as a guidline that has merrit. I think there are many factors that come into effect such as your preferred shot placement and bullet design. I have seen charts here or there that give a suggestion of the energy needed for different sizes of game animals. I would say its not a bad idea to limit yourself from going too far under the suggested energy levels per size of game, if your up in the air about it.

 

[FearNoWind]

Re: Bullet Energy and velocity

The term "bringing down" game is often misunderstood. You can bring down a deer, eventually, with some pretty shallow wounds that will cause it to bleed out and (if you're lucky) you can follow the blood trail to your kill. That is not, IMO, an acceptable hunter ethic. It is generally accepted that a certain amount of energy needs to be available in the projectile at the point of contact with the animal to bring it down humanely. The number I most often read is 1000 ft lbs. But if the bullet simply passes through the body mass without transferring that energy you may as well be shooting target arrows.
While you may find that ballistics calculations, including kinetic energy, give you a good idea about the long range capability of your rifle, it is also important to select bullets wisely. They need to expand to transfer energy (shock) but they shouldn't fragment. Unless, of course, your just hunting varmints.
I like Bergers for target - but not for hunting. I don't like their fragmentation characteristics and because they are lead core the lead fragments can be difficult (if not impossible) to remove from the game and I don't want lead fragments in my meat. My personal preference for hunting loads is Sierra.

 

[Kennibear]

The energy figure is a rough guideline. The velocity figure relates to the expansion requirements of the bullet.

Concerning energy: Most of the deer I have shot dropped to a 357 magnum with 700 ftlbs at the muzzle. I wasn't holding the revolver against their ribs. Enough is enough. Putting the bullet in the right place counts more than how much energy it has. Dropped a deer with one shot from my 30/06 after my partner hit it three times with a 7 mm RM. His went through the throat/ wind pipe and two through the off side front leg. Mine angled through from the left rear ham through the diaphragm and broke the right front shoulder before exiting. That deer showed no sign of being hit from the first three 7 mm's but anchored in place with the single 30/06. Don't get hung up on the energy. Bullet placement is far more important.

Concerning velocity: Velocity is driven by bullet construction. Enough velocity to expand the bullet but not so much the bullet fails by exploding when it hits. At - the - game velocity needs to be at or above the lower expansion threshold. As an example Nosler AB's need 1800 fps to expand but the new ABLR's require only 1300 fps. The Speer 375 caliber works fine at the 375 H&H velocity of 2700 fps but Speer does not recommend that bullet for the 378 Weatherby as it could be driven faster than 3300 fps and it would come apart like a varmint bullet.

Hope this clears it up somewhat.

KB