Using a S-12 to defend against an opponent wearing soft body armor

[Bounce12 407]

I can offer my experience, having been shot at close range with a 12 ga while wearing body armor (your results may vary LOL)......

 

While in the Army, almost 20 years ago, I was part of a joint task force to help destroy drug refineries in certain parts of Certral America. Obviously, the locals that worked there didn't like that too much. One of them opened fire with a 12 ga shotgun. He was standing in a doorway that I was right next to. He didn't see me.

Being young and stupid, I thought I'd take it away from him. I should have just shot him. Anyway, I rushed around the corner and struggled with him. I tried grabbing the barrel to leverage it up in the air while smacking the top of his right wrist. Unfortunately, the barrel was sawed off and my hand slipped. I tried regaining a hold on the barrel when he discharded it with my hand right over the end of the muzzle.

 

If you're not squeemish, here's a picture of my hand after it was cleaned up.

 

The shot, which was a Duplex round (birdshot and small buckshot) entered through my right palm and exited out my right wrist. It then hit the front/side of my chest/armpit area. About 2" to the right of my right nipple. I was wearing soft body armor there, so between my hand "slowing it down" and the kevlar, I wasn't hit as hard as I could have been.

 

Still, the impact cracked a rib and hurt like hell. Had the round not hit my hand first, I imagine it would have been more powerful. I guess you could say he "dis-armed" me.

 

I think my armor was threat level II, if I remember right. It was meant to be concealable and not like a flak jacket or heavy tactical hard armor with overlapping plates. Those types would probably have shrugged off the impact fairly easilly. Mine was worn under a load bearing vest.

 

 

 

I don't know if this helps anyone at all, but I felt I could offer my 2 cents, as it were.

 

 

Corbin

 

 

 

Man that looks like a Gaddis post!

 

Whew!

 

Thanks for your service - no shit!

 

You got a Purple Heart for that, right?

[lipadj46 2]

Just crunching the numbers in my head I disagree that a slug has enough momentum to knock a person over unless they were off balance or something. It would probably be a moot point at close range getting hit at close range even with a full SAPI plate the blast concussion, flash, noise, and burn would probably disorient the crap out of you.

I can respectfully understand you position, though i do not agree. I would think a hard surface would transfer momentum better than soft, though spreading it over a larger area. Still i can agree this is a entirly moot point.

 

Well with soft armor the problem is blunt trauma on a certain focussed small area. A shotgun slug does not have a very impressive magnitude of momentum when compared to things like a swinging bat, sledge hammer defensive tackle etc. (things that can knock a person over). The SAPI plate will just take that force and spread it out to some very tame pressures. I am afraid I have gotten this thread off on a tangent though.

[corbin 621]

Hey guys.

 

Getting shot will not knock you down from the impact. Not unless it had enough power to also knock down the person firing it. Now, don't get me wrong, if you take a shotgun blast to the chest, the pain will cause you to recoil and probably fall down, but the shot/slug can only impart as much kinetic energy as it's given. That means if you were theoretically bullet proof, you'd be hit with the same amount of force as the shell produces at recoil. It would be over a smaller area though, which would hurt more. Think of diving into a pool and doing a "back smacker" vs. slicing your hand open with a power jet washer.

 

Anyway, it's not like in the movies (or in Nailbomb's signature) where the guy goes flying backwards. It looks cool and makes the gun look more powerful, but that would be like the video game Mortal Combat where the finishing move is a punch that throws the opponent in the air and knocks his/her head off.

 

 

Corbin

[Nailbomb 10,221]

Hey guys.

 

Getting shot will not knock you down from the impact. Not unless it had enough power to also knock down the person firing it. Now, don't get me wrong, if you take a shotgun blast to the chest, the pain will cause you to recoil and probably fall down, but the shot/slug can only impart as much kinetic energy as it's given. That means if you were theoretically bullet proof, you'd be hit with the same amount of force as the shell produces at recoil. It would be over a smaller area though, which would hurt more. Think of diving into a pool and doing a "back smacker" vs. slicing your hand open with a power jet washer.

 

Anyway, it's not like in the movies (or in Nailbomb's signature) where the guy goes flying backwards. It looks cool and makes the gun look more powerful, but that would be like the video game Mortal Combat where the finishing move is a punch that throws the opponent in the air and knocks his/her head off.

 

 

Corbin

LOL yeah i knew that vid was horribly tacked on when i put it in the sig., did you notice its on the other side of a cat silencer from a videogame... the things have something in common that neither is real. but effectivly i can show you plenty of asshats not expecting what they are about to do falling over from shooting a shotgun on youtube. Are you expecting to be shot? while admitedly in a situation like this you should be(though avoiding it) chances are no.

[dannyfantasy2000 68]

Hey guys.

 

Getting shot will not knock you down from the impact. Not unless it had enough power to also knock down the person firing it. Now, don't get me wrong, if you take a shotgun blast to the chest, the pain will cause you to recoil and probably fall down, but the shot/slug can only impart as much kinetic energy as it's given. That means if you were theoretically bullet proof, you'd be hit with the same amount of force as the shell produces at recoil. It would be over a smaller area though, which would hurt more. Think of diving into a pool and doing a "back smacker" vs. slicing your hand open with a power jet washer.

 

Anyway, it's not like in the movies (or in Nailbomb's signature) where the guy goes flying backwards. It looks cool and makes the gun look more powerful, but that would be like the video game Mortal Combat where the finishing move is a punch that throws the opponent in the air and knocks his/her head off.

 

 

Corbin

LOL yeah i knew that vid was horribly tacked on when i put it in the sig., did you notice its on the other side of a cat silencer from a videogame... the things have something in common that neither is real. but effectivly i can show you plenty of asshats not expecting what they are about to do falling over from shooting a shotgun on youtube. Are you expecting to be shot? while admitedly in a situation like this you should be(though avoiding it) chances are no.

 

Yeah I spent a good 10 minutes one time trying to figure out what was going on with that "cat silencer" thing.

[Matt78 0]

Hey guys.

 

Getting shot will not knock you down from the impact. Not unless it had enough power to also knock down the person firing it. Now, don't get me wrong, if you take a shotgun blast to the chest, the pain will cause you to recoil and probably fall down, but the shot/slug can only impart as much kinetic energy as it's given. That means if you were theoretically bullet proof, you'd be hit with the same amount of force as the shell produces at recoil. It would be over a smaller area though, which would hurt more. Think of diving into a pool and doing a "back smacker" vs. slicing your hand open with a power jet washer.

 

Anyway, it's not like in the movies (or in Nailbomb's signature) where the guy goes flying backwards. It looks cool and makes the gun look more powerful, but that would be like the video game Mortal Combat where the finishing move is a punch that throws the opponent in the air and knocks his/her head off.

 

 

Corbin

LOL yeah i knew that vid was horribly tacked on when i put it in the sig., did you notice its on the other side of a cat silencer from a videogame... the things have something in common that neither is real. but effectivly i can show you plenty of asshats not expecting what they are about to do falling over from shooting a shotgun on youtube. Are you expecting to be shot? while admitedly in a situation like this you should be(though avoiding it) chances are no.

 

I never understood why so many people in our society have a problem with a quiet animal that kills vermin, yet are also enamored with small, loud, obnoxuious, helpless, over-domesticated, over-dependent canines.

 

I think that there should be a dog silencer video.

Edited April 17, 2009 by Matt78

[gothchick 0]

Just crunching the numbers in my head I disagree that a slug has enough momentum to knock a person over unless they were off balance or something. It would probably be a moot point at close range getting hit at close range even with a full SAPI plate the blast concussion, flash, noise, and burn would probably disorient the crap out of you.

I can respectfully understand you position, though i do not agree. I would think a hard surface would transfer momentum better than soft, though spreading it over a larger area. Still i can agree this is a entirly moot point.

My 2 Euros... Or, Ameros as the case may soon be.

 

A hard plate would transfer more kenetic energy over a wider area than soft armor. Therefore the felt blunt force would be less to the victim. Also something else to think about; If a slug has so much power as to throw a victim down to the ground, what is it doing to the guy shooting it? For every action there is an equal and opposite reaction... Or something like that. Lol.

Edited April 17, 2009 by gothchick

[Patriot12 11]

Just crunching the numbers in my head I disagree that a slug has enough momentum to knock a person over unless they were off balance or something. It would probably be a moot point at close range getting hit at close range even with a full SAPI plate the blast concussion, flash, noise, and burn would probably disorient the crap out of you.

I can respectfully understand you position, though i do not agree. I would think a hard surface would transfer momentum better than soft, though spreading it over a larger area. Still i can agree this is a entirly moot point.

My 2 Euros... Or, Ameros as the case may soon be.

 

A hard plate would transfer more kenetic energy over a wider area than soft armor. Therefore the felt blunt force would be less to the victim. Also something else to think about; If a slug has so much power as to throw a victim down to the ground, what is it doing to the guy shooting it? For every action there is an equal and opposite reaction... Or something like that. Lol.

This might be a mute point. It might be better to go for the neck and ankles with 3in OOO or OO copperplated buck. It might be better to defeat the armour where it is not worn.

[Matt78 0]

Just crunching the numbers in my head I disagree that a slug has enough momentum to knock a person over unless they were off balance or something. It would probably be a moot point at close range getting hit at close range even with a full SAPI plate the blast concussion, flash, noise, and burn would probably disorient the crap out of you.

I can respectfully understand you position, though i do not agree. I would think a hard surface would transfer momentum better than soft, though spreading it over a larger area. Still i can agree this is a entirly moot point.

My 2 Euros... Or, Ameros as the case may soon be.

 

A hard plate would transfer more kenetic energy over a wider area than soft armor. Therefore the felt blunt force would be less to the victim. Also something else to think about; If a slug has so much power as to throw a victim down to the ground, what is it doing to the guy shooting it? For every action there is an equal and opposite reaction... Or something like that. Lol.

 

That's what occured to me after posting yesterday. On the other hand, an individual only has so much area for the force to be distributed over. Let a force go to infinity, and have the area stay constant, and pressure goes to infinity as well. In other words, blunt force trauma can be lethal in non-penetrating scenarios with hard plates if the mass and velocity of the projectile are great enough. I suspect that if they ever develop hard body armor, light enough to be worn, that can actually stop a .50 BMG projectile, that the blunt force trauma would still kill the person.

[gothchick 0]

I can see that... But using that same logic, when I fire my S12 with magnum rounds, the recoil is transfered to a small area on my shoulder. While the force focused on my shoulder through the stock is litterally enough to leave me bruised for a week, it certainly isn't enough to knock me to the ground, or even knock me backwards more than a step...

Edited April 17, 2009 by gothchick

[Patriot12 11]

I can see that... But using that same logic, when I fire my S12 with magnum rounds, the recoil is transfered to a small area on my shoulder. While the force focused on my shoulder through the stock is litterally enough to leave me bruised for a week, it certainly isn't enough to knock me to the ground, or even knock me backwards more than a step...

The weight of your gun also offsets some of the opposite and equal reaction "recoil." The slug or bullet is also excellerating down the barrel until it run out of barrel. This exelleration also offsets this opposite and equal reaction. So the energy of a slug once it has exellerated to full velocity will have more energy than what it exhibited during recoil. Other wise you would have over 1000 pounds of recoil. This would be the case if excelleration was instantanious and barrel lenght was not needed.

[Matt78 0]

I can see that... But using that same logic, when I fire my S12 with magnum rounds, the recoil is transfered to a small area on my shoulder. While the force focused on my shoulder through the stock is litterally enough to leave me bruised for a week, it certainly isn't enough to knock me to the ground, or even knock me backwards more than a step...

 

Technically, it's not just your mass. Rather, it's your mass, plus that of your S-12 and all accessories attached to it.

 

Also, one must remember that one can be killed via blunt force trauma without being knocked backwards several feet as depicted in some asinine Hollywood film. One would most likely get hit and simply drop to the ground. The main distinction between your shoulder and the enemy's COM is that your shoulder is not a vital area, while his COM definitely is.

[gothchick 0]

I can see that... But using that same logic, when I fire my S12 with magnum rounds, the recoil is transfered to a small area on my shoulder. While the force focused on my shoulder through the stock is litterally enough to leave me bruised for a week, it certainly isn't enough to knock me to the ground, or even knock me backwards more than a step...

The weight of your gun also offsets some of the opposite and equal reaction "recoil." The slug or bullet is also excellerating down the barrel until it run out of barrel. This exelleration also offsets this opposite and equal reaction. So the energy of a slug once it has exellerated to full velocity will have more energy than what it exhibited during recoil. Other wise you would have over 1000 pounds of recoil. This would be the case if excelleration was instantanious and barrel lenght was not needed.

Well... Shotgun barrel length has nothing to do with projectile velocity... A 8" barrel will have the same velocity as a 19" barrel. And while the weapon mass itself is taking some of the recoil as it is discharged, so is the victim's metal plate body armor. So I think those two basically cancel each other out...

 

If I was sure that my hard plate body armor would stop a 12 gauge slug, I would have no problem standing in front of an oncomming slug. I doubt it would recieve any more injury than a nasty buise at most. Now with soft body armor, or no armor - forget it. I'm not into broken bones or gaping holes. Lol.

Edited April 17, 2009 by gothchick

[Patriot12 11]

I can see that... But using that same logic, when I fire my S12 with magnum rounds, the recoil is transfered to a small area on my shoulder. While the force focused on my shoulder through the stock is litterally enough to leave me bruised for a week, it certainly isn't enough to knock me to the ground, or even knock me backwards more than a step...

The weight of your gun also offsets some of the opposite and equal reaction "recoil." The slug or bullet is also excellerating down the barrel until it run out of barrel. This exelleration also offsets this opposite and equal reaction. So the energy of a slug once it has exellerated to full velocity will have more energy than what it exhibited during recoil. Other wise you would have over 1000 pounds of recoil. This would be the case if excelleration was instantanious and barrel lenght was not needed.

Well... Shotgun barrel length has nothing to do with projectile velocity... A 8" barrel will have the same velocity as a 19" barrel. And while the weapon mass itself is taking some of the recoil as it is discharged, so is the victim's metal plate body armor. So I think those two basically cancel each other out...

I speak the truth, although sometimes distorted.

[Matt78 0]

I can see that... But using that same logic, when I fire my S12 with magnum rounds, the recoil is transfered to a small area on my shoulder. While the force focused on my shoulder through the stock is litterally enough to leave me bruised for a week, it certainly isn't enough to knock me to the ground, or even knock me backwards more than a step...

The weight of your gun also offsets some of the opposite and equal reaction "recoil." The slug or bullet is also excellerating down the barrel until it run out of barrel. This exelleration also offsets this opposite and equal reaction. So the energy of a slug once it has exellerated to full velocity will have more energy than what it exhibited during recoil. Other wise you would have over 1000 pounds of recoil. This would be the case if excelleration was instantanious and barrel lenght was not needed.

 

What you're describing is known as the impulse-momentum theorem, which I should have recalled as being relevant to this discussuion (it's been a while since my last university Physics course). This really is the key to solving the confusion here: http://en.wikipedia.org/wiki/Impulse

 

According to the impulse momentum-theorem, the force delivered to a body is inversely proportional to the amount of time taken for the projectile to decelerate (or accelerate, in the case of firing).

 

So a bulllet, or a fist, or whatever, that hits a body, that stops suddenly (on the order of milliseconds) will deliver a huge force. This force, divided by the area that the force is delivered over (whether just the wound area, or the whole torso, as would be the case for hard armor), equals the pressure received.

 

Now, a bullet, or a fist, or whatever, hitting something soft, like a cushion, or airbag, or whatever, will take a longer period of time to decelerate, and therefore deliver a smaller force.

 

Patriot 12 points out the key point here: firing a projectile from 0 to muzzle velocity in x amount of time is NOT symetrical to said projectile going from muzzle velocity (well, slightly less than muzzle velocity, depending on how far away the enemy is standing) down to zero in y amount of time (where x and y are NOT equal times).

Edited April 17, 2009 by Matt78

[Patriot12 11]

I can see that... But using that same logic, when I fire my S12 with magnum rounds, the recoil is transfered to a small area on my shoulder. While the force focused on my shoulder through the stock is litterally enough to leave me bruised for a week, it certainly isn't enough to knock me to the ground, or even knock me backwards more than a step...

The weight of your gun also offsets some of the opposite and equal reaction "recoil." The slug or bullet is also excellerating down the barrel until it run out of barrel. This exelleration also offsets this opposite and equal reaction. So the energy of a slug once it has exellerated to full velocity will have more energy than what it exhibited during recoil. Other wise you would have over 1000 pounds of recoil. This would be the case if excelleration was instantanious and barrel lenght was not needed.

 

What you're describing is known as the impulse-momentum theorem, which I should have recalled as being relevant to this discussuion (it's been a while since my last university Physics course). This really is the key to solving the confusion here: http://en.wikipedia.org/wiki/Impulse

 

According to the impulse momentum-theorem, the force delivered to a body is inversely proportional to the amount of time taken for the projectile to decelerate (or accelerate, in the case of firing).

 

So a bulllet, or a fist, or whatever, that hits a body, that stops suddenly (on the order of milliseconds) will deliver a huge force. This force, divided by the area that the force is delivered over (whether just the wound area, or the whole torso, as would be the case for hard armor), equals the pressure received.

 

Now, a bullet, or a fist, or whatever, hitting something soft, like a cushion, or airbag, or whatever, will take a longer period of time to decelerate, and therefore deliver a smaller force.

 

Patriot 12 points out the key point here: firing a projectile from 0 to muzzle velocity in x amount of time is NOT symetrical to when the projectile going from muzzle velocity (well, slightly less than muzzle velocity, depending on how far away the enemy is standing) down to zero in y amount of time (where x and y are NOT equal times).

Damn, thats what I was trying to say. I literally couldn't have said it better my self.

[gothchick 0]

Wow, very good new perspective to think about. So what would the proper ratio be between projectile (acceleration/ kenetic energy from the weapon) to (projectile deceleration/ kenetic energy transfered to the victim)?

Edited April 17, 2009 by gothchick

[Patriot12 11]

Wow, very good new perspective to think about. So what would the proper ratio be between projectile (acceleration/ kenetic energy from the weapon) to (projectile deceleration/ kenetic energy on the victim)?

Believe it or not, there are actually record firing tables that exsist of this purpose. You might be able to google it.

[Nailbomb 10,221]

LOL yeah i knew that vid was horribly tacked on when i put it in the sig., did you notice its on the other side of a cat silencer from a videogame... the things have something in common that neither is real. but effectivly i can show you plenty of asshats not expecting what they are about to do falling over from shooting a shotgun on youtube. Are you expecting to be shot? while admitedly in a situation like this you should be(though avoiding it) chances are no.

 

I never understood why so many people in our society have a problem with a quiet animal that kills vermin, yet are also enamored with small, loud, obnoxuious, helpless, over-domesticated, over-dependent canines.

 

I think that there should be a dog silencer video.

Who said i had any problem with cats? or animals at all? My problem is with people, especialy preachy animal lovers. I want to go on a rant about PETA now just becaws of you. Can you understand its a 'video game'? I don't care if it was a baby fetus on the end of the barrel I would find it funny. Does that make me pro-choice? NO. It means i have a twisted sense of humor.

[Matt78 0]

Wow, very good new perspective to think about. So what would the proper ratio be between projectile (acceleration/ kenetic energy from the weapon) to (projectile deceleration/ kenetic energy transfered to the victim)?

 

Well, for deceleration into the enemy, I'd say that it's probably well under 1 millisecond (note: this sort of thing is empirical, meaning it's not practical to get from equations, but rather, should be measured experimentally, in my previous post, I thought that a few milliseconds is reasonable, but on second thought, that does seem a bit long for a bullet, slug, or shot hitting a body). It's actually probably on the order of tens or hundreds of microseconds.

 

For the period of time between the projectile(s) leaving the cartridge, and leaving the muzzle, one uses basic kinematics formulas. First, you assume uniform acceleration from 0 up to muzzle velocity (a reasonable assumption) because the math is a bear if the acceleration is non-uniform. Let's take a muzzle velocity of 1600 feet/second (the muzzle velocity of slugs that I am ordering off the internet this weekend), and a barrel length of 19''.

 

First, for uniform acceleration from 0 to v, the relevant kinematics equation states that the average velocity during that time is simply v/2, or 800 feet/second = 9,600 inches/second. We are interested in average velocity because the time spent accelerating is simply the barrel length divided by the average velocity. So here, we have 19 inches divided by 9,600 inches/second = 0.001979 seconds = 1.979 milliseconds ~= 2 milliseconds.

 

Let's assume that it takes 100 microseconds (e.g., one tenth of a millisecond) for the slug to decelerate into the enemy. Then, the ratio would be 20. The case that is x times faster involves x times the force, so here the force would be 20 times as great.

 

We're going to have to find empirical data on this to be sure. For now, we know how to calculate one of the numbers. To compute the ratio, we'll need the other number. As I said, the figure must be well under 1 millisecond.

Edited April 17, 2009 by Matt78

[Matt78 0]

LOL yeah i knew that vid was horribly tacked on when i put it in the sig., did you notice its on the other side of a cat silencer from a videogame... the things have something in common that neither is real. but effectivly i can show you plenty of asshats not expecting what they are about to do falling over from shooting a shotgun on youtube. Are you expecting to be shot? while admitedly in a situation like this you should be(though avoiding it) chances are no.

 

I never understood why so many people in our society have a problem with a quiet animal that kills vermin, yet are also enamored with small, loud, obnoxuious, helpless, over-domesticated, over-dependent canines.

 

I think that there should be a dog silencer video.

Who said i had any problem with cats? or animals at all? My problem is with people, especialy preachy animal lovers. I want to go on a rant about PETA now just becaws of you. Can you understand its a 'video game'? I don't care if it was a baby fetus on the end of the barrel I would find it funny. Does that make me pro-choice? NO. It means i have a twisted sense of humor.

 

I'm not a PETA fan. My girlfriend's shih tzu just really gets on my nerves a lot. I wish that she preferred cats.

[SCBOWLES 0]

Now I get it, I thought the cat was in heat and looking for a little relief.

[SCBOWLES 0]

how about some of us Atlanta saiaga owners get together and run some balastic tests. I,m equiped to reload shotgun shells so we can get creative

[gothchick 0]

LOL yeah i knew that vid was horribly tacked on when i put it in the sig., did you notice its on the other side of a cat silencer from a videogame... the things have something in common that neither is real. but effectivly i can show you plenty of asshats not expecting what they are about to do falling over from shooting a shotgun on youtube. Are you expecting to be shot? while admitedly in a situation like this you should be(though avoiding it) chances are no.

 

I never understood why so many people in our society have a problem with a quiet animal that kills vermin, yet are also enamored with small, loud, obnoxuious, helpless, over-domesticated, over-dependent canines.

 

I think that there should be a dog silencer video.

I don't care if it was a baby fetus on the end of the barrel I would find it funny. Does that make me pro-choice? NO. It means i have a twisted sense of humor.

OMG, lol. I think we're two peas in a pod. Lol. Edited April 17, 2009 by gothchick

[vbrtrmn 167]

So, I'm confused, will a shotgun kill a cat dressed in soft body armor or not?

[Patriot12 11]

So, I'm confused, will a shotgun kill a cat dressed in soft body armor or not?

I want to hear more about the impulse-momentum theorem and less about shooting cats with abortes fetuses.

[gothchick 0]

Wow, very good new perspective to think about. So what would the proper ratio be between projectile (acceleration/ kenetic energy from the weapon) to (projectile deceleration/ kenetic energy transfered to the victim)?

 

 

Well, for deceleration into the enemy, I'd say that it's probably well under 1 millisecond (note: this sort of thing is empirical, meaning it's not practical to get from equations, but rather, should be measured experimentally, in my previous post, I thought that a few milliseconds is reasonable, but on second thought, that does seem a bit long for a bullet, slug, or shot hitting a body). It's actually probably on the order of tens or hundreds of microseconds.

Well, let's not get too hasty here. The projectile doesn't just STOP and dump ALL it's kenetic energy into the victim all at once when it hits a victim. It creates a wound tunnel, bounces around inside the victim's body, or dents plate armor, or is absorbed via kevlar fibers, might even exit straight through the victim losing valuable energy transfer, etc...

 

 

For the period of time between the projectile(s) leaving the cartridge, and leaving the muzzle, one uses basic kinematics formulas. First, you assume uniform acceleration from 0 up to muzzle velocity (a reasonable assumption) because the math is a bear if the acceleration is non-uniform. Let's take a muzzle velocity of 1600 feet/second (the muzzle velocity of slugs that I am ordering off the internet this weekend), and a barrel length of 19''..

All the tables I've seen show 12 gauge muzzle velocity around 1100 or 1200 give or take. It's not a fast moving round at all compared to a rifle, but more on the order of a pistol.

 

 

First, for uniform acceleration from 0 to v, the relevant kinematics equation states that the average velocity during that time is simply v/2, or 800 feet/second = 9,600 inches/second. We are interested in average velocity because the time spent accelerating is simply the barrel length divided by the average velocity. So here, we have 19 inches divided by 9,600 inches/second = 0.001979 seconds = 1.979 milliseconds ~= 2 milliseconds...

Whew, I'll take your word for it on this one. :-)

 

We're going to have to find empirical data on this to be sure. For now, we know how to calculate one of the numbers. To compute the ratio, we'll need the other number. As I said, the figure must be well under 1 millisecond.

Very nice post. :-) Edited April 17, 2009 by gothchick

[Nailbomb 10,221]

I don't care if it was a baby fetus on the end of the barrel I would find it funny. Does that make me pro-choice? NO. It means i have a twisted sense of humor.

OMG, lol. I think we're two peas in a pod. Lol.

3 Gaddis has been holding it down for us for a while befor we ever showed up.

[Matt78 0]

how about some of us Atlanta saiaga owners get together and run some balastic tests. I,m equiped to reload shotgun shells so we can get creative

 

Well, we'd probably need really good time lapse photography equipment (a high quality digital camera connected to a laptop?) to measure the amount of time between initial impact and complete rest. We'd also need something that approximates bone and flesh, or put kevlar on a dummy (whatever we want to simulate).

 

On the other hand, it may be possible to infer the deceleration time by observing the damage to the target (e.g., measuring the depth of the indentation).

Edited April 17, 2009 by Matt78

[Matt78 0]

http://www.sciencedirect.com/science?_ob=A...2e665c8d90e2421

 

That is sort of relevant to the case we're considering, though the velocities are a bit higher, and the application is slightly different ("Study on terminal effects of dense fragment cluster impact on armor plate. Part I: analytical model ").

 

It does look like the deceleration times involved in a supersonic projectile hitting something hard, like armor, are indeed on the order of microseconds or tens of microseconds, meaning that the perpetrator feels anywhere from hundreds up to thousands of times the force you do even if wearing soft body armor.

Edited April 17, 2009 by Matt78