9mm vs .45ACP

Had a chipmunk running around in front of my house this morning while I was out front.

Thought to myself "of all days to wear my loose leg shorts..."

:eek:
 
I have to admit, more words will rhyme with nine within a beat than forty-five. You gots me there. Think you could use that coachgun in my pic for that pesky chipmunk as well. :p
 
"All else being equal, momentum tends to correlate well with penetration."

Obviously, though, not all else is equal anymore when a round with far less momentum will both expand AND penetrate as deeply as the round with the greater momentum.

Comparative momentum goes out the window when you start designing bullets to expand and penetrate reliably within their particular velocity band.
 
Yup, if you can't control all the other variables then it's not possible to compare two rounds based purely on momentum.

The new, engineered ammunition uses energy and momentum in conjunction with bullet and material design to achieve the expansion and penetration required by whatever spec the designer is trying to attain. Within that paradigm, the only time that momentum becomes an issue is if there's not enough available to make the design work properly within the framework of available materials and the state of the art of bullet design.
 
To put this to bed. 9mm and .45ACP are both sufficient enough to get the job done in this day and age with modern bullet technology.

-fin-

That should be the last discussion! :D

SIG 1911 XO / SA 1911 custom / Colt Gold Cup / SIG P226 e2 / Browning High-power / Beretta PX4 Storm / G34 / G19 / G21 / G22 / G30 / S&W M-19 / Hk USP 40 / Rem 870 / Rock R. AR-15

sent from my Android
 
"That should be the last discussion!"

BUT BUT BUTBUTBUTBUTUBTUBTUBUTBUT!!!

THE .45 IS HEAVIER! IT'S BETTER BECAUSE IT'S HEAVIER! AND BIGGER! BIGGER IS ALWAYS BETTER! BIGGER WON'T SHRINK, BUT SMALLER MAY NOT GET BIGGER!!!!

JOHN MOSES BROWNING! AMERICA!

9MM? HITLERNAZI! EVIL! EEEEEEEEEEEEEEEVVVVVVVVVVVIIIIIIIIIIILLLLLLLLLLLLLLLLLLLLLLLLLLL!!!


And so forth and so on.
 
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LMAO

Yes and the great Miami shootout from the 80's remember? lol..

I mean hell, I have 9mm bullets with my breakfast to help wake me up. They're so cute when they're young and harmless. Especially in speer gold dot +p O.O

SIG 1911 XO / SA 1911 custom / Colt Gold Cup / SIG P226 e2 / Browning High-power / Beretta PX4 Storm / G34 / G19 / G21 / G22 / G30 / S&W M-19 / Hk USP 40 / Rem 870 / Rock R. AR-15

sent from my Android
 
THE .45 IS HEAVIER!
ST. JOHN MOSES BROWNING! (PBUH). AMERICA!
9MM? HITLERNAZI! EVIL EUROWEENIES!
And so forth and so on.

And when we've stomped that dead and burned it with fire, sure as anything a new 9v45 thread will start within a week.

It's like the "unkillable enemy" nightmare.

( Yes, hanging around gunboards for over a decade has left me cynical.)
 
"""It's like the "unkillable enemy" nightmare."""

Hate those dreams. They're worse than the dreams...you know what. Never mind.

SIG 1911 XO / SA 1911 custom / Colt Gold Cup / SIG P226 e2 / Browning High-power / Beretta PX4 Storm / G34 / G19 / G21 / G22 / G30 / S&W M-19 / Hk USP 40 / Rem 870 / Rock R. AR-15

sent from my Android
 
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THE .45 IS HEAVIER! IT'S BETTER BECAUSE IT'S HEAVIER! AND BIGGER! BIGGER IS ALWAYS BETTER! BIGGER WON'T SHRINK, BUT SMALLER MAY NOT GET BIGGER!!!!

JOHN MOSES BROWNING! AMERICA!

9MM? HITLERNAZI! EVIL! EEEEEEEEEEEEEEEVVVVVVVVVVVIIIIIIIIIIILLLLLLLLLLLLLLLLLLLLLLLLLLL!!!

Pretty sure I have never seen a forum quote this great.
 
Sure it is simple physics. For dealing with things that arent bullets. And even then its not such a great indicator.

Take for example the 7.62 Tokarev round. Small bullet, high velocity, not a lot of momentum.

The Germans called it the russian icepick because it penetrated like mad, generally far better than the heavier 9mm.
 
It works great for comparing bullet penetration, but only assuming that everything else is equal.

Comparing 9mm to 7.62x25 using only momentum as an indicator probably won't work because the caliber is different. It may or may not provide useful information when comparing bullets of the same caliber if the bullet profile is different, when comparing expanding rounds of one variety within a caliber to expanding rounds of another variety within a caliber, when the velocity difference is sufficient to cause one of the bullets to fail but not the other, or for any sort of comparison where something other than momentum is varied.

Like energy, bullet weight/mass, caliber, sectional density, velocity, bullet profile, bullet construction, etc., it's a part of the puzzle of terminal ballistics. Like all of those things, it's a very small part of the puzzle.
 
It works great for comparing bullet penetration, but only assuming that everything else is equal.



I am not so sure about that. I am in the middle of reading Quantitative Ammunition Selection after seeing it being talked about on some other 'sites. The author has put together an interesting model based on momentum that can be used to calculate how far a bullet will penetrate, how much it will permanently crush and how fast it will be going if it exits a body part like a bicep.

I am gonna have to read it at least a couple of more times to get all that he has to say 'cause its pretty intense mathwise.
 
.45 for the win. Besides, 1911's were meant to shoot .45's which already makes it a superior round. Just a little biased, but why not.
 
"It works great for comparing bullet penetration, but only assuming that everything else is equal."

NOTHING, absolutely NOTHING, is even remotely close to "equal."

Bullet weight is equal? No.

Bullet diameter is equal? No.

Bullet ballistic coefficient is equal? No.

Bullet sectional density is equal? No.

Bullet velocity is equal? No.

Bullet form factor is equal? No.


The only way all else would be equal would be if you were comparing two identical bullets.

Which is the better stopper? The .45 ACP 230-gr. FMJ or the .45 ACP 230-gr. FMJ?

I mean hell, if all else were equal, a hand-held Qutonium P Plutonium-powered Disruptor makes a GREAT concealed carry piece.

What? There's no such thing as a Qutonium P Plutonium-powered Disruptor?

Well I guess all else isn't equal then.
 
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