When people are asking about high power cartridges, do they mean high velocity, high energy, or high knock down power? You can have a cartridge that has one but not the other two or two but not all three. I think this term is a little over used or over generalized. Any thoughts?

In my opinion, when people ask about high power cartridges they are asking about ALL THREE, high Velocity, high Energy, and Knock Down Power. However, I agree with the previous article. I think this term High Power is over used.

Power is relative to either the animal being shot or the shooter. Lots of people will consider a 357 magnum or 40 S&W a high power cartridge or even a 44 Rem Mag. And yes, all of these are very effective personal protection cartridges at close range. But what does high power really mean? Man, I don't know! Ask the person who is asking the question, what they are trying to figure out!!

As you increase velocity you increase energy. This is a given. Knock down power is really relative to mass, so as you increase mass while maintaining a similar level of velocity, you will increase knock down power. For example a 22 magnum has the same energy as a 38 special. But a 38 special has more knock down than a 22 magnum. Knockdown is better understood as momentum.

A secondary element of knock down is bullet expansion and energy transfer. This is because most bullets fired from handgun cartridges do not expand as dramatically as bullets fired from rifle cartridges. Thisis because they do not have the high level of velocity. Additional, a lot of people shooting automatic handguns use full metal jacket bullets. So the bullets don't expand at all. They just pass right through the target.

In my opinion, High power is relative to the target or animal. To increase power and knock down, first I recommend substantially increasing the bullet weight and try to increase velocity where possible. Take it for what it is worth, but that is my recommendation.