Where are you guys seeing info that shows 9mm having similar ballistic characteristics as .40? From what I'm seeing, current 9mm is good, but it still is not performing the same as a .40. For instance, TNOutdoors9 did a comparison of Federal HST in .40, 9mm and 9mm +P. When you compare the areas and penetration of both expanded and projectile size before expansion, the .40 is always bigger. Per his results, a .40 has 27% greater frontal area passing through the target before expansion. A standard 9mm has only 94% the surface area after expansion and a +P has 94% the frontal area. When you calculate the volume of the damage path that a .40 Federal HST has, it comes to about 3.64 cubic inches of damage path. The standard pressure 9mm will pass through 2.95 cubic inches and the +P will pass through 2.72 cubic inches. That means that a .40 Federal HST passes through more than 23% volume than a standard pressure 9mm and 33% more than the +P 9mm round.
Those are not insignificant differences. Mind you, I'm not a .40 zealot. I like shooting the .40 and I like reloading for it, but I carry a 9mm and a .45 more than I carry a .40. I understand the point that on rounds 2 and up, you will probably see more accurate placement of a 9mm round than a .40 round, but I don't think the .40 is outside of combat accurate.
My question is, where is the data that shows a 9mm round produces a near equivelant amount of damage as a .40? Granted, TNOutdoors9 should not be considered the be all, end all of testing but his scientific rigor is not bad.
Again, I'm not arguing the point, just trying to understand if the data is accurate or if we are just hashing internet lore regarding the capabilities of a 9mm pistol round.
Dead is dead, stopped is stopped. If two different handgun rounds are both capable of performing as desired, one can then begin to look at other factors such as reduced recoil and the benefits thereof. Its that simple.
"Knockdown power", "Stopping power" and "One shot stop" statistics are bull**** and folklore. A 9mm direct hit to the heart is worth ten .40 hits that miss the heart by 1/16".
It's easy to get caught up in numbers.
" The standard pressure 9mm will pass through 2.95 cubic inches and the +P will pass through 2.72 cubic inches."
If this is true, why does the +P exist? It provides more recoil and less performance. It exists because some people insist that velocity matters in handgun ammo. If penetration, expansion and weight retention are sufficient, velocity is meaningless.
Carry whatever you want but I urge you to carry the round you are most accurate with which will perform as desired. Just don't forget that hitting small moving targets isn't easy and rarely happens quickly, meaning capacity matters.
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