Originally Posted by Doc3402
I really wish someone would do a controlled test of a 9mm with the common 110 gr hollow point and the .357 magnum with a 158 gr hollow point loaded to the same velocity and fired out of a test barrel to show the difference in penetration. It would make this stuff a lot easier to understand for many people.
I would absolutely agree that a 115gr vs 158gr going at the same velocity,the 158gr would have more penetration.
I understand that between projectiles with equal energy,the one that has more mass will be "better".
I'm not an expert of any stripe,but I understand that energy is important to make momentum.I understand that something with more mass will have more resistance to a change in its inertia as well,and would also have more momentum,given equal energy imparted to it.
However,what I sort of don't grasp is how a projectile that is different in mass only by at most a few dozen grains (1 grain = 0.064 gram) as in the example of 115gr vs 158gr could have such a tremendous difference in inertia as to affect terminal penetration to the degree that one becomes clearly superior over the other.
What I do grasp is that given similar weights,say a 125gr .357 vs a 124gr 9mm,but different velocities,.357 going 1500 to 1600fps (
) and the 9mm doing about 1200fps,with resulting energy being strongly in favor of the magnum,I think it would be clear that the magnum has a pretty hefty advantage.
Around 300ftlbs more advantage that can be used to build and maintain inertia.
So here you see velocity giving more energy -and thus for sure more penetration- to bullets of almost the same size.
Like I said,I'm no expert,but I can see that energy is as important as mass.
As for me,I think I'll still be sticking to solids no matter what caliber I choose to use.
The most memorable part of that video was the .40 JHP's failure to penetrate even given what was excellent (or lucky) shot placement.
.40 s&w is not light on energy,mass,or diameter,in fact,some consider it a perfect blend of all 3 (short of the 10mm,of course).
Over and over and over again I keep seeing and reading of incidents where HP's of all sorts in all kinds of calibers from all different kinds of designs both old school and modern do absolutely unpredictable things in real life shootings.
I'd probably go with some kind of flat nosed hardball in .45 around 180-200gr,I'm gonna stick with 165gr flat nosed hardball in .40 (Remington makes the hottest and best shooting in my gun),and I'll probably stick with 9x19 nato at 124gr for my 9s.The 147gr flat nose looks good too.
But I think this video was the straw that broke the camels back for me as far as JHP and HP designs are concerned.