View Full Version : Stopping power of .38s and .45s

January 13, 2006, 01:44 AM
Considering a few things, I've heard all my life that "a .45 caliber bullet from a long or acp will lift you off your feet and knock you back" :cool: :p

Now, I know better. HOWEVER, it is said in response to this "if it doesn't knock you off your feet when shooting it, it isn't going to knock down the target man."
Considering that, if you aren't standing just right braced for the gun fire from your weapon, you can be knocked back a little stumbling.
If your target is not braced against the bullet, then one shot I would think from a .45 or even .38 could stumble him back a bit. 2 to 4 shots quickly placed from a .45 or maybe even .38 could indeed knock a man back. I know the first time I shot my .45 1911 firing all 7 shots I was almost swept off my feet because of the recoil until I learned to lean into it. Same thing happen to a girl that went shooting with us this past weekend from just one (and each one afterward) shot from my .38 Official Police. With each shot she would take she would stumble back a tad and my hand would have to catch her back and try to encourage her to lean forward.
NOW, combine the above statements with the fact that the target is not only getting the equal energy from the recoil of your gun, he is also getting a bullet drilled into him and probably even one that is mushrooming inside him (HP or HS) tearing his flesh and crushing bone. This could also cause reaction such as when you get hit with a fist. It isn't the fist that knocks you back but the pain from it. Also, the target is most likely not expecting the force of the bullet hitting him. He has no time to brace himself, if he spots you at all he is more likely going to be trying to duck for cover. If he decides to charge you (for some crazy reason) then he might just keep comming then (as he is resisting the energy of your bullet) unless you hit a vital spot.

January 13, 2006, 10:19 AM
A large number of "one shot stops" result from psychological reasons, shock, etc. That's why even a .25 in the toe may be recorded as a one shot stop. You certainly can't count on this, so that's the reason so much is debated about caliber, type of bullet, mass, velocity, and especially shot placement.

January 13, 2006, 11:47 AM
I feel the same about HP vs ball ammo. With high speed rounds, say 9mm, a ball round can go in and out and if it hits nothing vital the victim may ignore the fact that he was shot. With a good JHP round the bullet decelerating in the body as the bullet mushrooms, tearing flesh, nerves and organs. Gunshot victims say getting shot feels like a punch, but it will not knock you off your feet. Its like getting cut with a razor vs getting cut with a jagged,serrated blade, you will feel it more if flesh is torn and not cleanly sliced. I think a BG will be more shock, scared, and more likely to surrender getting wounded with a JHP or a heavier caliber round because he will feel it, instead of a light fast ball ammo going in and out with little physical pain. That is stopping power for me, not the notion that you can push over someone with a big, powerful round.

Glenn E. Meyer
January 13, 2006, 12:08 PM
The force is not enough to knock someone back.

Being off balance is different or having a psychological effect is probably the case when someone topples.

I've seen little old ladies shoot 45s and never move their feet. I've seen big men trying to posture and state that a 45 almost tore their arm clean off. :barf:

January 13, 2006, 12:12 PM
where do these myths come from? The notion that "A .38 or .45 are larger rounds that's shock will knock someone down even if it is just a limb wound to the arm or leg." Most notably in movies is the movie Shane in which "the more realistic era of western movies began with Shane, where the power of a .45 knocks a man back." Of course we see Stonewall Tory and Jack Wilson flying back 6 feet when getting shot. Seems to me, older movies (which all my friends say are unrealistic) got it right. When you see somene shot in old mvoies they looked shocked and then grab their chest or stomach or wherever they were shot and crumple down in pain and ultimately die.
I've heard historical books, gun dealers, and even some gun experts say things like "the shock power of a .45 will knock you down even if it is just a limb hit".
Is there truth to it only in what I said in the original post above?

Glenn E. Meyer
January 13, 2006, 02:29 PM
People have to be educated. Unfortunately, there is not a real, scholarly reviewed technical press about gunfighting.

While we have legitimate experts with experience and expertise, most writing meet the standard of the popular press. There is little use of modern data collection and analyses.

What information that does exist usually is not read by causal weekend warriors. Do you scan the med data bases on wound characteristics, the criminological literature on gun usages, the technical police and military literature or human factors literature?

Some people do and they present their works in those journals or at high end tactical conferences. However, on the Internet, mythological statements, anecdotes and baloney can reign supreme.

I go to the NTI and hear some in charge of a state's tactical training tell us that they found no difference betwee quality 9s, 40s, and 45s. However, has stuff like that ever stopped the 9 vs 45 discussion? No.

It would neat if there was a legitimate technical textbook on gun usage. Oh, well.

January 14, 2006, 08:02 AM
A physical reason that I would imagine could cause a stumble back would probably be because it takes Very high PSI to exist to propel the bullet to the FPS it will leave the gun at. A LOT of that energy is wasted the process and is not transfered to the bullet. Furthermore, I would think part of the reason the recoil of the weapon can cause recoil reaction on your body is that you ARE prepared for it. You lock you hands and arms in front of you which directs the force back through your body. If you were to somehow create some sort of set up where you could fire a gun from just above your waist, no hands needed, I would think your belly would easily absorb the recoil. Your lower torso can conform better to absorb impact better than your straight arms.

January 14, 2006, 11:48 AM
Irrespective of all the bovine fecal material devoted to stopping power in the rags and popular books, there is no such thing.
Placement power is what you need.


Para Bellum
January 14, 2006, 01:25 PM
...not even a 12ga with 00 Buckshot lifts you out of your boots, does it?

January 14, 2006, 01:53 PM
OK, I might be a nerd, but I like Myth Busters. They did an episode one time on being knocked back when shot (probably do disprove the old movies where the BG flies back 5 feet). They stuck their dummie up on some kind of sling and shot it with several guns. None of them knocked the dummie off the sling until they got to a 12 guage, and it wasn't dramatic, the dummie just slumped over and fell straight down. They showed how much pressure was required to knock the dummie off of the sling and it wasn't much. It all comes down to shot placement. The body of the BG absorbs the shock regardless of the size of the round.

January 14, 2006, 02:13 PM
Here are some videos.

308 round in the chest (http://www.dt-concepts.com/mg/308-chest1.mpg)

44 mag round in the chest (http://www.dt-concepts.com/mg/44mag-chest.mpg)

308 round into a 23.5lb log (http://www.dt-concepts.com/mg/shootingthelog.mpg)


January 14, 2006, 02:19 PM
What an idiot.... Who volunteers to be shot?

January 14, 2006, 02:35 PM
Umm... both of those guys? :D

Seriously though, whether or not they are idiots was only one question answered by the video. The other question was whether or not a bullet will not knock someone flying through the air or even knock them down.


January 14, 2006, 02:46 PM
I was pretty moved when I shot my first .45, but it was more of an emotional reaction. :p

The girl pushing over the log in that last vid was hilarious.


January 14, 2006, 03:47 PM
Those guys in the video crack me up. :p Demonstrating getting shot with a live round.

January 15, 2006, 03:59 PM

We should get t-shirts

"verything I learned about physics came from watching daytime television"

January 15, 2006, 06:00 PM
"verything I learned about physics came from watching daytime television"

Yea - it is a shame. As a country, our people fall very short in math and reasoning skills.


January 15, 2006, 06:31 PM
The formula is called Pounds-Feet.

The energy necessary to move a 1 lb weight 1 foot.

Simple formula. Muzzle velocity times bullet weight in lbs (230gr bullet divided by 7000=.0328lbs) A 230gr at velocity of 900fps=29.57 pounds-feet. A 9MM 115 at 1400fps=23 pounds-feet.

Makes things much more realistic:)

Formula was originally published in Field and Stream, probably in the 1930s. it can be found in Elmer Keith's 'Keith's Rifles for Large Game', published in 1946.

January 15, 2006, 06:32 PM
The .38 handguns of the time proved to have little stopping power on the islamic tribesmen of the Philippines, thus the .45 ACP/1911 was adopted. From that time until the 9mm was adopted, there was little complaint about stopping power.

January 15, 2006, 08:16 PM
Spot on, KC. It is called momentum and it is commonly expressed as lb-fl/sec.

The formula was determined quite some time before Field & Stream magazine, but that was probably the first real exposure the shooting community had to it.

Newton is credited for the 3 laws of motion and his work was based upon that of Galileo.


Az Qkr
January 15, 2006, 08:17 PM
"If your target is not braced against the bullet, then one shot I would think from a .45 or even .38 could stumble him back a bit"

Stumbling back from firing a 45 or 38 is the result of lack of coordination and motor skills, certainly not from a lack of bracing to fire those calibers.

My 8 year old nephew who was 65 pounds could fire both calibers flat footed, leaning back at the waist to hold up the firearms. He didn't brace, he didn't stumble, or anything else like that, probably beciase he didn't know any better and had no preconceived ideas that there some some "power" there he should know about.

Stumbling? Not from the force of either of those two rounds, braced or not braced.

"2 to 4 shots quickly placed from a .45 or maybe even .38 could indeed knock a man back."

Yes, and if that occured, it would be a phychological reaction to the event, not anything to do with impulses on the body.

"NOW, combine the above statements with the fact that the target is not only getting the equal energy from the recoil of your gun, he is also getting a bullet drilled into him and probably even one that is mushrooming inside him (HP or HS) tearing his flesh and crushing bone.

The recoil impulse of the gun is caused by the mass of the bullet being forced through the barrel by edxpanding gases [ a controlled explosion ]. No one being shot is experiencing that if hit.

"It isn't the fist that knocks you back but the pain from it."

Are you saying that if I make a fist, plant it firmly on your chest and start to gradually push you to the rear that somehow the "pain" is knocking you back? It might be time for you to realisitically reconsider the thought processes you have on this subject.

"Also, the target is most likely not expecting the force of the bullet hitting him."

People have tested being shot with rifle rounds while standing on one leg without ANY effect or being knocked back, falling over or any other such effects.

People REACT to being shot in various ways. The bullet is not moving them at all due to any "impulse" generated to their body by the bullet.

If people are stumbling back while firing a 45 or 38, they need to PUT THE GUN DOWN AND MOVE BACK AWAY FROM IT, until they have someone with enough knoweldge show them it is not a physiological event thats causing them to stumble.

Robin Brown