I am wondering how many pounds are needed to humanely and cleanly put down an elk. I saw on hornady's website that a 180 Grain SST in 30-06 puts out around 1500 ft/lbs at around 500 yards. With relatively good bullet placement, will this down an elk? or should it be closer? thanks you.
I disagree with some commentators about energy...
The energy of the bullet does
two things:
- flatten the soft-nosed bullet on impact, and
- push/break everything that gets in its way until it stops.
To be most effective on heavy game, a bullet needs to expand on imppct or very soon thereafter or it's just being like FMJ. There are some armoured game where FMJ is appropriate but all big game I know about are shot with high velocity bottle-necked rounds that need to expand to do enough damage for a quick kill. A tiny hole may not even kill and it usually won't kill quickly unless it's to CNS. Large bore is another matter entirely. Muzzle-loaders of large bore don't need to expand much to cause a huge wound channel. .30-'06 does.
Most expanding bullets are made of lead because it's a soft metal and the force of impact will deform it and do more damage as it passes through game. The ability to expand depends on velocity of impact because the force of impact varies roughly as the square of the velocity. If the bullet doesn't expand soon it may never expand in the animal, because it slows down as it does damage to the animal.
So, the energy that's critical here is not the tiny amount required to flatten lead (Ever used a hammer to whack a lead bullet? How many ft-lb does that take? It's a few inch-pounds...), but the energy needed to push the expanded bullet through the animal. Through the ribs is much less than through a shoulder, by a good factor. 1500 ft-lb is enough to push an expanded bullet through an elk doing grievous bodily injury as intended. For deer, about 900 ft-lb will do but in both cases, more is a bit better because there could be bush in the way or less than optimal placement. Bad things happen. However, the folks who figure 3000 ft-lb is better are just wasting energy as much of that will be dumped in forest/land on the other side after passing through.
More critical than energy at impact is velocity. Every soft-nosed bullet has some minimum velocity required to mushroom on impact. That's related to it's energy but weakly. A heavy bullet and a light bullet both need at least 1600 ft/s velocity to have much chance of mushrooming with a copper jacket. Not all jackets are created equal. Pure lead will mushroom down to 1100 ft/s or a bit less. A Sierra Match King will not mushroom in an 8 inch poplar fired from a 7mm Rem Mag from 70 yards away. That jacket is too tough. Sierra used to give useful ranges for its bullets starting at around 100 yards all the way to 600 yards for various muzzle-velocities. The jackets were too fragile at higher velocities but were useful at long ranges down to ~1800 ft/s or so. That was OK, because we could use two or more weights of bullets for hunting, heavy RN for close in and something pointed and BT for the longer ranges. If you are going to take a long shot you need to be sure of accuracy, placement, expansion and energy. That's a tall order.
