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Self-Defense & Pistol Wounding Factors (PDF)

PostPosted:Fri May 30, 2008 3:32 pm
by Wynder
Thanks to Myopic for passing along this document which covers the topic of factors relating to effectively using your pistol in self-defense against a live target.

http://deloc.org/docs/FBI_Handgun_Wounding_Factors.pdf

Re: Self-Defense & Pistol Wounding Factors (PDF)

PostPosted:Fri May 30, 2008 3:52 pm
by Wynder
This is great... The guy talks about how stopping power is basically a fallacy and the real factor is caliber, but here's a great example:
Goddard amply proves the fallacy of "knock-down power" by calculating the heights (and resultant velocities) from which a one pound weight and a ten pound weight must be dropped to equal the momentum of 9mm and .45ACP projectiles at muzzle velocities, respectively. The results are revealing.

In order to equal the impact of a 9mm bullet at its muzzle velocity, a one pound weight must be dropped from a height of 5.96 feet, achieving a velocity of 19.6fps. The equal the impact of a .45ACP bullet, the one pound weight needs a velocity of 27.1 fps and must be dropped from a height of 11.4 feet. A ten pound weight equals the impact of a 9mm bullet when dropped from a height of 0.72 inches (velocity attained is 1.96 fps), and equals the impact of a .45 when dropped from 1.37 inches (achieving a velocity of 2.71 fps).
So, if you want to feel the 'stopping' power of a .45, lay down, grab a 10lbs weight and drop it from an inch and a half from your body, I guess. Moral of the story? I think I need to buy me an XD chambered in .40 or .45. ;p

Re: Self-Defense & Pistol Wounding Factors (PDF)

PostPosted:Sat May 31, 2008 9:21 am
by myopicvisionary
All other things being equal, a big bullet beats a smaller one. That said, HP technology has really progressed in the last decade so its OK to have less than a 105mm howitzer in your pocket.

Re: Self-Defense & Pistol Wounding Factors (PDF)

PostPosted:Sat May 31, 2008 5:48 pm
by LordJim
This is great... The guy talks about how stopping power is basically a fallacy and the real factor is caliber,
There's a video floating around YouTube that does a really decent job at illustrating the fallacy of 'stopping power'. The video is a guy taking a .44 magnum at 6 feet while standing on one leg. He didn't even sway.

Of course the gentleman is wearing a vest, and perhaps some other time we can have the discussion about just how wise that was.

-
Jim

Re: Self-Defense & Pistol Wounding Factors (PDF)

PostPosted:Sun Jun 01, 2008 8:06 am
by stephpd
Yeah, it always kills me when you see in the movies some guy getting blown off his feet and flying back 20 feet.

Basic physics. For every action there is an equal and opposite reaction. To do that you'd need a gun that also knocks the shooter back by the same amount. The force felt by being hit with a bullet is no greater then the felt recoil of shooting. Recoil springs absorb some of this when cycling the slide.


Now that's not to say that the bullet won't perpetrate and do damage. They do. And bigger bullets put bigger holes in the target. JHP's make bigger holes then FMJ. And the spinning barbs of some JHP's can increase the damage.

Re: Self-Defense & Pistol Wounding Factors (PDF)

PostPosted:Thu Jul 10, 2008 9:10 am
by Mr Jody Hudson
With modern hollow points of the highest quality; there is little difference in penetration and expanded diameter. The primary difference is in the hydrostatic shock that is temporarily experienced by the recipient as a result of the combination of speed, diameter, weight and penetration -- magnified of course by placement (where it hits and what it tears up).

There are still many more opinions, some opinions look like mathematical discussions at first but they often end up as primarily opinions.

Personally, I like the Corbon DPX the best by far, in all the primary self defense calibers. However for reasons that I do not understand, when shooting calibrated geletin blocks the .357 sig and the 10 mm both show incredibly greater damage to the geletin than other rounds that have almost identical expanded diameter and penetration.

The reason I like DPX is that it almost always has a little more penetration, a little more expanded diameter and a little more speed giving more hydraulic shock AND it has the best results going through all the testing barriers of anything I have seen - by far... glass, leather, layers of clothing, etc. all seem to just get out of the way. It also has the cutting edge flower as it expands. It is expensive.

Therefore; I often opt for my second and third choices the Ranger and the Speer +P Gold Dot HP -- which can more often be found in affordable quantities.

Jody

Re: Self-Defense & Pistol Wounding Factors (PDF)

PostPosted:Thu Jul 10, 2008 10:52 am
by stephpd
Mr Jody Hudson wrote:The primary difference is in the hydrostatic shock that is temporarily experienced by the recipient as a result of the combination of speed, diameter, weight and penetration
Hydrostatic shock is part of the myth.

I've read all three parts of that FBI report. The link above is the third part and a summary of the first two. The authors conclusion is that an ill place shot with a 230gm bullet fired from a .45 acp has shone to be more effective then an ill placed 115 or 147gm 9mm.

It dispels the David v Goliath myth.

Bullet placement is the most important followed by bullet weight. Velocity as to creating a larger temporary cavity didn't seem to help.

To me this study and the one they did back in the early 1900's both show that for handguns a .45 or larger is king. That's why old muzzle loaders and flintlocks were .50 cal. There has never been a study done that proved that the speed of the bullet was a factor in handgun deaths.

The same can be said for rifles. Caliper trumps speed every time. Once you get past mach 2 speed makes very little difference. Caliper and weight is what wins.

Many of our troops that are in battle say the same. Give them a .30 cal rifle and a .45 handgun and more of the enemy would be dead. The .223 AR-15 and the 9mm handgun doesn't stop or kill quick enough.

But the been counters say different. :x

Re: Self-Defense & Pistol Wounding Factors (PDF)

PostPosted:Thu Aug 21, 2008 5:42 am
by myopicvisionary
Yeah, it always kills me when you see in the movies some guy getting blown off his feet and flying back 20 feet.
That's why I get ill every time that POS Sharon Stone movie "The quick and the dead" comes on TV. A .45 Colt bullet picks Gene Hackman up and flips him over in a backward somersault!

Re: Self-Defense & Pistol Wounding Factors (PDF)

PostPosted:Thu Aug 21, 2008 8:13 am
by Sprat
up close and if you have to shoot it will be up close, a 25 cal will do the job. don't know about you folks, but for me its not about killing.

off to the range, gunsmith range day

sprat

Re: Self-Defense & Pistol Wounding Factors (PDF)

PostPosted:Tue Feb 17, 2009 8:45 am
by LordJim
LordJim wrote:
This is great... The guy talks about how stopping power is basically a fallacy and the real factor is caliber,
There's a video floating around YouTube that does a really decent job at illustrating the fallacy of 'stopping power'. The video is a guy taking a .44 magnum at 6 feet while standing on one leg. He didn't even sway.

Of course the gentleman is wearing a vest, and perhaps some other time we can have the discussion about just how wise that was.

-
Jim
I just managed to find this by accident (it's the video I mentioned in the post above). Enjoy.

http://www.thefirearmblog.com/blog/2008 ... 44-magnum/

-
Jim