Velocity, Mass, Ft-lbs and all that jazz


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Darebear
June 5, 2011, 01:19 PM
First off I am going to apologize, I do not want to ask the old 45 vs 9 question but I am confused so I need the help of experienced shooters.

I own a 9mm (hk p2000) and recently brought a hk45c (this is my love child)... I was under the impression that .45 acp ammo was hovering in the higher Velocity numbers. 900+ fps and 400-500+ Ft/Lbs out of the muzzle. Maybe I'm looking in all the wrong places but all the ammunition I did research on produced numbers that aren't impressive to me. Gold Dot, Gold Dot short barrel, Winchester PDXI and other defensive loads are pushing numbers around what a 40 s&w or 9mm +p+ would produce. In some cases I found 40 S&W muzzle energy to be higher than .45 acp muzzle energy.

I'm not concerned that I am under-gunned with the .45 acp. I know and respect it's power and agree it's a great self defense round. All I'm wondering is with current technology and bullet manufactures now making a amazing product in all calibers, is there much advantage of the venerable .45 over the 9mm(top shelf defensive 9mm loads) when it comes to muzzle energy/velocity?

Again I apologize for bringing up the old arguement.

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rcmodel
June 5, 2011, 01:47 PM
when it comes to muzzle energy/velocity?Unless you are trying to pick between a .38 Spl and a .454 Casull for hunting brown bear?

Muzzle energy is a totally useless measurement of handgun bullet performance.
Energy dump at SD handgun velocity just doesn't make any meaningful difference.

A 230 grain .45 ACP JHP has been designed to expand at perhaps as little as 800 FPS.
A 165 grain .40 S&W JHP perhaps 1,000 FPS.

If you shot a living target in the vital zone with either one, the results would be the same. A big bleeding hole.

However, it might be important to note that the .45 ACP pistol replaced the .45 Colt revolver in military service when the Army still fought with horse calvary.

Either one was expected to stop or disable a charging horse or rider.
They already knew from experience & testing a smaller faster bullet couldn't get the job done.

rc

ugaarguy
June 5, 2011, 01:58 PM
Force = mass x velocity^2 while momentum = mass x velocity. Encounter a barrier and we're now primarily dealing with inertia (momentum) rather than energy (force). Sectional density is also another factor, and sd is more important when dealing with harder barriers than softer barriers.

Darebear
June 5, 2011, 02:26 PM
Force = mass x velocity^2 while momentum = mass x velocity. Encounter a barrier and we're now primarily dealing with inertia (momentum) rather than energy (force). Sectional density is also another factor, and sd is more important when dealing with harder barriers than softer barriers.
Could you perhaps explain that a little better please?

Also in a self defense situation is it plausible that me or any average american citizen will be shooting through barriers?

rcmodel
June 5, 2011, 02:28 PM
Here, play with this.
It's a lot easier to use then Chinese Algebra.

http://www.handloads.com/calc/quick.asp

rc

murf
June 5, 2011, 02:46 PM
darebear, i really think you are getting caught up and confused by a bunch of numbers. if you want to know which bullet performs better, wrap a few phone books in duct tape, shoot it with both bullets and see for yourself how they perform.

suggest you do this in a safe location (not your garage, or living room). fwiw

murf

Darebear
June 5, 2011, 04:10 PM
darebear, i really think you are getting caught up and confused by a bunch of numbers. if you want to know which bullet performs better, wrap a few phone books in duct tape, shoot it with both bullets and see for yourself how they perform.

suggest you do this in a safe location (not your garage, or living room). fwiw

murf
Yes I'm still all new to this. Only have been shooting for a year. But if the muzzle energy numbers and velocity aren't important then why do manufactures put the numbers on the packaging? I watch alot of TNToutdoor videos on youtube and he always mentions velocity and muzzle energy. What is important when it comes to caliber damage?

murf
June 5, 2011, 04:57 PM
for the same reason car manufacturers advertize horsepower - it sells their product.

what is important is that you and your loved-ones don't get hurt in a bad situation. that places a lot of importance on the reliability of your ammo and the reliability of you to place that bullet in the correct spot every time.

keep listening to the old-timers on the high road. they won't steer you wrong. and quit worrying about the numbers.

murf

Friendly, Don't Fire!
June 5, 2011, 05:03 PM
It only goes without saying that, if they are souping-up the .40 caliber and the .38 Special that while they are busy souping-up these smaller calibers, they are also souping up the .45 ACP to which they are apparently comparing!

When one looks at it in those terms, I want the "souped-up version" of .45!

Darebear
June 5, 2011, 06:25 PM
It only goes without saying that, if they are souping-up the .40 caliber and the .38 Special that while they are busy souping-up these smaller calibers, they are also souping up the .45 ACP to which they are apparently comparing!

When one looks at it in those terms, I want the "souped-up version" of .45!
Can someone point me to some souped up .45 loads? The only hot .45 load I've seen is Corbon's load.

Shadow 7D
June 5, 2011, 06:35 PM
Roll your own

in the end, handguns aren't all the impressive, and the differences are that great, yet, in this arena you have rounds that are twice a 'powerful' as a different caliber, yet fail to produce HALF the 'power' of a rifle.

Thats why in the end, I prefer to shoot the calibers I like, for whatever reason, with ammo that is designed to work in that caliber. Yes, in my pocket mouse's I'm not going to be attacking a squad of Assault Troopers or zombies, but really folk, who is?

Get into reloading and you can roll nice easy target round, and pumped up rounds, all for less than what a box of premium will cost.

918v
June 5, 2011, 06:50 PM
Why not compare the hole sizes and not the muzzle energies?

Shadow 7D
June 5, 2011, 06:53 PM
Ok, so taking thousandth of an inch...

918v
June 5, 2011, 06:55 PM
Why don't you try hunting elephants with a 30-06. Afterall, it's only a couple thousands of an inch.

Shadow 7D
June 5, 2011, 07:11 PM
Naw, I'd rather use a .38
it's bigger after all...
actually read an interesting story of an elephant that was put down with a .38, after the helicopter pilots ran out of ammo on the gunships strafing it...

Like I said
Thats why in the end, I prefer to shoot the calibers I like, for whatever reason, with ammo that is designed to work in that caliber. Yes, in my pocket mouse's I'm not going to be attacking a squad of Assault Troopers or zombies, but really folk, who is?

Use an appropriate caliber, that you like, and reload to maximize what it can do, and make the round you want/like.

Darebear
June 5, 2011, 09:05 PM
So muzzle energy and velocity means nothing. What matters is what loads expand reliably? I just thought a round pumping out numbers like a 40 s&w at 1100 fps and 450+ ft/lbs would do more damage than a "big boy caliber" like a slow .45 at 800 fps and 400 ft/lbs. I read articles that claim that the .357 sig is quickly gaining a "one-shot stop" reputation and I assumed it's because of the velocity of this round. But if velocity means nothing then I'll stick with the bigger round in all situations.

Again, I am not dissing the .45... I know it is a great self defense round, but these velocity and muzzle energy numbers have to stand for something right?

ugaarguy
June 5, 2011, 09:10 PM
Could you perhaps explain that a little better please?

Also in a self defense situation is it plausible that me or any average american citizen will be shooting through barriers?
When I say barrier, I mean anything other than air. Soft barriers would be flesh, hard barriers would be things like your refrigerator. The point is, don't get hung up on energy numbers alone.

918v
June 5, 2011, 09:16 PM
So muzzle energy and velocity means nothing.

Exactly. Pistol rounds produce so little energy it does nothing for stopping power.

918v
June 5, 2011, 09:18 PM
Also in a self defense situation is it plausible that me or any average american citizen will be shooting through barriers?

Of course. There are cars, walls, glass, etc. everywhere. If someone is shooting at you from a car, will you not return fire? What about a door frame?

Darebear
June 5, 2011, 09:45 PM
When I say barrier, I mean anything other than air. Soft barriers would be flesh, hard barriers would be things like your refrigerator. The point is, don't get hung up on energy numbers alone.
Got it. Thanks.

ugaarguy
June 5, 2011, 09:54 PM
No problem Darebear. Any of the three you listed will work. Just find a gun that you shoot well in one of those calibers.

HK Jake
June 6, 2011, 01:25 AM
Energy numbers don't mean jack in the common handgun calibers!

Check this out: http://ammo.ar15.com/project/Self_Defense_Ammo_FAQ/index.htm

And: http://www.m4carbine.net/showthread.php?t=19887

FWIW, I tend to carry the heavier bullets in each caliber for best penetration and expansion.

swinokur
June 6, 2011, 05:08 AM
Shot placement rumps all. All the rounds discussed will work.

I like Federal HST .230g .45 +p if you want a recommendation

If penetration is above 12" for the 9,mm 40 or 45 then hole size can be an important factor. Bigger wound channel may mean more tissue damage and faster bleed out.

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