The 9mm vs 45 ACP Debate: A Visual Aid...

"Incidentally I also tested 357 mag from the LCR and found that it wasn't much faster than 38 special +p from that '1.875 barrel. But kicked a lot more and had a huge muzzle flash."

If it kicked a lot more, the bullet had a lot more momentum. Physics 100. If you shoot blanks in a gun that have a HUGE amount of flash and bang, there will be almost no recoil at all.
 
Mike I totally agree. That's why I was so surprised when the chronograph said differently.
I eventually concluded that the 357 had a very fast acceleration in a shorter amount of time because of the recoil. But that it still wasn't up to even near its potential before the bullet left the barrel. Hence the chronograph showing only ~70 fps faster than 38 special +p
 
If it kicked a lot more, the bullet had a lot more momentum. Physics 100. If you shoot blanks in a gun that have a HUGE amount of flash and bang, there will be almost no recoil at all.
You are incorrect about the bullet momentum. You have failed to consider the mass of the unburned powder and the gas. They also have momentum as they exit the barrel. That can result in more actual recoil while the bullet itself is traveling no faster than a more efficiently designed cartridge/barrel length combination.
 
If it kicked a lot more, the bullet had a lot more momentum. Physics 100. If you shoot blanks in a gun that have a HUGE amount of flash and bang, there will be almost no recoil at all.
If that were true, "Physics 100" would deny the existence of rocket propulsion.

Firearm recoil is driven by the mass and velocity of the bullet, the mass and velocity of the other ejecta, and the mass of the firearm.
 
A pistol isn't intended as and never has been an offensive weapon.
"Never has been" may not be quite right. Those Colt Paterson revolvers that had been ordered by the Texas Navy may not have been intended for use as offensive weapons, but I believe they were employed as such by Captain Jack Hays and the Texas Rangers.
 
I'm mostly staying out of the 9mm vs 45 acp debate -- been there, done that more than once. Suffice it to say that 35 years ago, it wasn't much of a debate, IMO, because of bullet design. The 230 gr FMJ .45 was clearly superior to 9mm ball. Hollow point performance was not up to where it is now so many preferred the .45. That has changed. While I mostly carry a .45 (hollow points), that is because I prefer 1911s and it is the better caliber for that platform. However, I am quite comfortable carrying 9mm in non-1911 platforms.

As to those touting the energy dump of the 10mm, keep in mind that bullets are often designed for performing at certain velocities. For example, Underwood's 180 gr. Gold Dots may suffer jacket separation because they were designed for velocities lower than the 1330 fps or so you may get out of a pistol using Underwood's load. See https://www.youtube.com/watch?v=sl_n_miLfbY. I have a 10mm but don't carry it because I can't see any additional benefit for the added recoil of the 10mm (I feel the same way about .40 S&W). I'm not convinced the energy dump from a 10mm means that much -- penetration and expansion mean more and the 10mm doesn't necessarily perform any better than other calibers for defensive purposes.
 
I did NOT say that gel and flesh act in the same way, that's ridiculous. What I said was that a bullet engineered for gel will react similarly to one that hits flesh.. Hollow points don't care what fluid medium they hit, if a fluid compound gets into the hole, it will expand. You should have read the rest of the posts where I carefully explained that gel isn't meant to replace flesh and that it's just a scientifically calibrated substitute that gives good enough results for testing and research.

I also said nothing about "knockdown power" or eighties television. It's really very simple. When you injure someone badly enough, he will very likely go into shock, and drop. If you hurt him badly enough, blow out his spine, tear a hole through his kidneys, generally speaking,your opponent will stop shooting back because he can't control his body well enough to continue fighting that's not a reference to knockdown power, it's a simple reference to the physical effects of injury and trauma.

As everyone here knows, The 44 magnum will not blow someone's head clean off, it isn't even a guaranteed kill. A kid tried to commit suicide by his father's 44 and put a round through his heart. He got to a trauma center in maybe thirty minutes, they patched up the damage, and he survived. But, when his parents heard the shot and found him, the trauma of a shot through the heart had left him unconscious.
 
"Never has been" may not be quite right. Those Colt Paterson revolvers that had been ordered by the Texas Navy may not have been intended for use as offensive weapons, but I believe they were employed as such by Captain Jack Hays and the Texas Rangers.

That's kind of splitting hairs. The pistol was designed as a defensive side arm. That's not to say that it couldn't be used as an offensive weapon in certain circumstances, but it's original intent was not thus.

There's so much argument about "Should I carry a 9mm?" or "Do I need a .45 to kill an assailant, thus save my own life?" etc., etc. The answer is you carry whatever gets YOUR job done. A pistol is defensive, nothing more. 99.99% will never have cause to draw a pistol in defense of their own lives. If you're in a war zone, or LEO, your needs are different. If you live in Pleasant Valley, USA, you probably don't need a pistol at all. If you are living where you need to be on alert at all times and need a calibre weapon that will incapacitate with a "snap shot," then, quite frankly, you need to move.
 
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A pistol is defensive, nothing more.
Agreed.

99.99% will never have cause to draw a pistol in defense of their own lives.
Irrelevant. Once the need arises, the need is usually the same.

One exception is that a sworn officer may have a need to shoot through plate glass to enforce the law.
 
"You have failed to consider the mass of the unburned powder and the gas."

For handguns, the mass of the unburned powder and gas is trivial compared to the bullet mass. Do the blank experiment.
 
"I'm not convinced the energy dump from a 10mm means that much".

Ask a hunter who hunts man-sized game at close ranges, and who has experience with 10mm AND .45acp, .40S&W, and 9mm.
 
For handguns, the mass of the unburned powder and gas is trivial compared to the bullet mass.
The mass is small, but the velocity of the gases is very high.

Do the blank experiment.
Blanks do not behave the same way in terms of effluent mass and velocity.

Consider too that combustion and expansion beyond the barrel (or rocket motor nozzle) does not contribute to thrust--just to noise and flash.
 
8 Rounds of 45 or 10 rounds of 40 will become the new normal in states were magazine capacity is limited. 9mm as a primary defensive arm only makes sense in compact guns and where mag capacity or lower recoil is an advantage. rc
 
I agree. 45 or 40 make more sense in CA than elsewhere because of their dumb mag restrictions. But if you live in a place where you can put 19 rounds of 9mm in a full size gun, 10 rounds of 45 in the same sized gun makes less sense. Just my 2 cents. Ymmv
 
SMH... Another caliber debate :(.

I carry 9mm or larger. I have carried .32 back before the commonality the modern 9mm pocket pistol. Now that I can carry a 9mm almost as easy... Well I will.

I do prefer a more powerful caliber when practical. 40s&w is a great compromise, 10mm is great, 45 is a classic and plenty powerful enough... With that being said, 9mm is enough caliber for me but its not a "go to" unless convenience of carry is important. I do not try to convince myself that is just as good as 40 or 45.

Terminal ballistics are a funny thing. Imperial research has been attempted but there are simply too many variables. I will say that a simple reading of ft-lbs of energy is heavily skewed toward velocity. If you simply judge off of fpe, 243 winchester is about in the same tier as 45-70 in rifle calibers (within 10% of fpe). If my only two options were to be shoot with 85gn 243 or 300gn 45-70... I'll roll the dice on 243. I suspect most others here would take the same gamble.

There is the capacity, ease of recoil debate. I understand both play a role... But honestly, unless I'm on duty, I feel adequately armed with 6 rounds of 38+p (9mm equivalent... Basically). When on duty I can carry as many spare mags as I need so as long as I can hold 8 per mag I'm good. A 1911 will do that.
 
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Whiskey, you are absolutely right. Velocity of the projectile counts for more when you are calculating KE. It's simple you look up the equation, add the numbers, and do the math.

Kinetic energy, high KE, is more involved with destruction of the target. Look at a prairie dog with a .223, and behold the destruction. Shoot a prairie dog with a 30-30, and the results will be very different. A 22-250 can blow a crater into steel plate, but a 45-70 will only dent it at the worst.

Consider the large hard on collider. A few alpha particles at near light speed disintegrate matter. That's destructive energy that's unimaginable.
 
Brian, "destruction of target" is relative and higher KE does not always equate to more effective. Again compare 45-70 and 243. Very close and comparable in KE if you compare 85gn 243 and 300gn 45-70. I don't think many would argue against 45-70 being more powerful than 243. Much more so than the 5% difference in KE.

More KE does not equal more effective.
 
I did not say that it is more effective. I said that at the point of impact, the force will be more destructive in nature. The 45-70 hits with a thump and penetrates deeply. The .243 goes in and tears it's way through, shedding energy rapidly.

The reason that steel silhouette shooters use heavier solid bullets is that the want every bit of energy to be used to knock over the steel plate.
 
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