Thread: Knockdown power

Originally Posted by 7.62

As others have pointed out, knock down power in terms of the bullet’s kinetic energy literally knocking an animal over, is a myth. The reason an animal gets poleaxed is generally when the bullet has caused catastrophic damage to the brain, spinal column, or the autonomic plexus; it wasn’t dropped by straight out kinetic energy.

But in my mind kinetic energy is still critical for a quick kill. There’s been a bit of discussion in this thread about hydrostatic shock, temporary wound channels, and blood pressure spikes to the brain all causing immediate incapacitation, even though the bullet may not have directly hit and damaged the CNS. I’m no pathologist but this makes a lot of sense to me. If we compare a bow hunter making a clean double lung shot on a red hind at 50yd, to a rifle hunter also making a lung shot on a hind at 150yd, what is the likely outcome? In the archery scenario the arrow has arrived with minimal energy, maybe 100ftlb, but it has still inflicted massive damage to the lungs and associated blood vessels. Despite this the hind still runs 75yd until she expires from blood loss. And what of our mate with a 270 or 308 running some SSTs at a decent speed? Well the hind 150yd away has been completely flattened. The SST has arrived with over 2000ftlb of energy and caused massive damage to the lungs, and has also instantly incapacitated the hind. Was this caused by hydrostatic shock or some other mechanism? I have no idea but kinetic energy is a good thing!

The shock wave from a high velocity bullet cannot be underestimated for 'stunning' the animal which then bleeds to death and dies while laying on the ground. We have all seen a 'stunned' animal that we thought had been killed instantly, leap to its feet before the eight count and leave the ring. This 20 second link shows the shockwave: https://www.youtube.com/watch?v=osNWIP7tg3Y