Bullet Penetration Options

[John84]

Don't see any reason to doubt George. He does, after all, have the tee-shirt! Squirrel is, however, correct but the Field Service Pocket Book goes into things even more finely:

Steel plate, best.........................................7/16"
Steel plate, ordinary mild, or wrought iron....3/4"
Shingle......................................................6"
Coal, hard..................................................6"
Brickwork, cement mortar............................9"
Brickwork, lime mortar.................................14"
Chalk.........................................................15"
Sand, between boards or in sandbags............18"
Sand, loose..................................................30"
Hard wood, e.g. oak......................................38"
Earth, free from stones (unrammed)..............40"
Soft wood, e.g. fir.........................................58"
Clay............................................................60"
Dry turf or peat............................................80"

Failing that - duck!

Cheers,

Ian

Beats me after reading all these statistics, how the soldier’s bible, princess Mary's Christmas tin, etc, I have often read about, seemed on occasions to stop a bullet.

John.

[IanA]

As has been said, even an overcoat might stop a bullet if it was fired from far enough away!

Ian

[John84]

As has been said, even an overcoat might stop a bullet if it was fired from far enough away!

Ian

Ian, could you tell me what is far enough away ...I haven't got a clue.....Although I think have read somewhere that men could be killed up to a mile away from where the shot was fired.

John.

[IanA]

I refer you to post #13

However, the trusty Field Service Pocket Book does say that the maximum range may be taken as about 3,700 yards.

Ian

[Coldstreamer]

Figures seem to fit; I recall seeing an infantry section (in the early 70s) chop down a fairly mature fir tree with a GPMG. It was done as an object lesson in choosing cover from fire.

Ive seen a gimpy cut through breeze blocks - scary stuff

Ian

[Coldstreamer]

Hello

Off on a slight tangent

Any one seen Mythbusters on SKY (discovery ?)

They had an episode where they fired various calibre rifles into water - I think the penetration was very poor - the 50 calibre was ineffective after 3 feet ....

Ian

[John84]

I refer you to post #13

However, the trusty Field Service Pocket Book does say that the maximum range may be taken as about 3,700 yards.

Ian

So just over two miles, the killing range should be easily one mile then???....Like you Ian, I am no ballistics expert.

John.

[JGM]

Out of interest when would a helmet stop a bullet? I am thinking quite a distance away from the guns.
JGM

[Coldstreamer]

Hello

I think the helmet was to stop shrapnel etc..... and to boil water in....

Ian

[Compo]

Hello

Any one seen Mythbusters on SKY (discovery ?)

They had an episode where they fired various calibre rifles into water - I think the penetration was very poor - the 50 calibre was ineffective after 3 feet ....

Ian

Er.. seems even senior officers don't always read the previous posts.
See my earlier submission.
Regards

[duckman]

Out of interest when would a helmet stop a bullet? I am thinking quite a distance away from the guns.
JGM

That sounds like it should start "I say, I say, I say..."

When it hit at an angle? I doubt a perpendicular hit would be stopped at any normal range, but that was why the Brodie was such a flat pan shape, to increase the likelihood that any strike would be at a flat angle.

Think tank armour.

Regarding human bodies and water and such, as has been mentioned, there is plenty of non-watery stuff to deflect a bullet, start it tumbling and lose most of its penetrative ability. Since the function of a bullet is to transmit as much energy as possible into the target, this is a "good thing", though it makes issues of "penetration" a bit meaningless.

To reiterate in more gruesome tones: A bullet that punches a neat hole in you and exits while retaining some of its energy increases the chances of simple surgery saving your life. A bullet that penetrates, starts to tumble and stays in you has transferred all its energy (with all that entails for damage to neighbouring organs) will probably require more surgery to fix - to pick out the fragments if nothing else. Whether that results in more immediate fatalities (from worse wounds) or more resources tied up in caring for those severe wounds, it a win-win situation for the shooter.

It's related to the trend towards smaller calibre ammo. There are several reasons (cost, weight etc) but one is definitely that a small calibre round does a better job of transferring its energy to the target.

[auchonvillerssom...]

The link I posted earlier on this thread doesnt seem to have been read by many, lovely explanation of penetration by full metal jacketed rounds....kill rates of AK47 compared to shotguns. Although some of the casulaties were chidren so body disruption patterns might be different.

Mick

[Justin Moretti]

Does that mean, I wonder, that a bullet travels at the same velocity at point blank range as it does at 500 yards?

No.

Finding a formula to calculate this took up a great deal of my time as a schoolboy, and eventually (much later) I just bought a computer program on the internet.


FYI, the Textbook of Small Arms 1929 gives the remaining velocity at 500 yards for the MkVII bullet (174 grains or 11.34 grams, 2440fps at the muzzle) as 1500fps; at 1000 yards, 1000fps; at 1500yd, 800fps; at 2000 yards, 600fps. There are complicated laws regulating all of this, the important factor being that the rate of loss of velocity is directly proportional to the velocity times some constant. The nature of that constant changes with the shape of the bullet (blunt versus round-nosed versus various degrees of pointy-ness) and changes drastically below the speed of sound.

Note the almost 1000fps velocity loss in the first 500 yards, the 500fps lost down to just under the speed of sound (around 1100fps under standard sea level conditions), and the mere 200fps lost in each of the last two 500 yard steps to the magic 2000 yard mark. At 2500 yards, the figure is 430fps; at 3000, 300fps, showing that the loss rate of velocity continues to fall off with reducing speed. At 300fps, the bullet will still yield a nasty wound; at 430fps, it is carrying enough energy to penetrate into the body and to kill with a lucky shot. Nobody wants to risk this.

The .303 MkVII round had a feature which had the effect of enhancing its energy delivery to the target; the tip of the bullet was filled with a low-density material (by design, aluminium, though substitutes were tried). On striking the target, the back end (where the centre of gravity was) would try to become the front end, encouraging the bullet to tumble and thereby to slow down and dump more energy into the target. This does not eliminate the possibility of pass-through.

While not germane to WW1 discussions, the MkVIII boat-tailed bullet, which came along later, had many of its advantages in the subsonic realm, altering the value of that velocity-loss multiplier and extending its range hugely, while in WW2, firing tests to determine damage done to aircraft at LONG range were performed at very SHORT range (to ensure hits and not waste valuable trials time) with cartridges that had to be deliberately underloaded to produce a lower striking velocity.

[IanA]

So............let me get this right. If I stand 500 yards away it wont hurt?

Ian

[Coldstreamer]

Er.. seems even senior officers don't always read the previous posts.
See my earlier submission.
Regards

Oops - - sorry -- I know who the other viewer is now..great program

[duckman]

The .303 MkVII round had a feature which had the effect of enhancing its energy delivery to the target; the tip of the bullet was filled with a low-density material (by design, aluminium, though substitutes were tried). On striking the target, the back end (where the centre of gravity was) would try to become the front end, encouraging the bullet to tumble and thereby to slow down and dump more energy into the target. This does not eliminate the possibility of pass-through.

While not germane to WW1 discussions, the MkVIII boat-tailed bullet, which came along later, had many of its advantages in the subsonic realm, altering the value of that velocity-loss multiplier and extending its range hugely, while in WW2, firing tests to determine damage done to aircraft at LONG range were performed at very SHORT range (to ensure hits and not waste valuable trials time) with cartridges that had to be deliberately underloaded to produce a lower striking velocity.

At risk of stating the obvious, the force Justin describes, but didn't label unless I missed it, is usually called 'drag' - Wikipedia has some quite good articles on it for the uninitiated (they are a bit technical, though). It changes with the square of the velocity (ie double the speed = 4 times the drag), hence the massively larger "velocity-loss multiplier" at higher fps.

Coefficent of drag is determined mainly by the shape of the bullet, and pointed/round-nosed bullets will have differing characteristics at different speeds (esp depending on supersonic/subsonic velocities). The boat tail design of the Mark VIII reduces wake turbulence, and therefore drag, and is particularly important at subsonic velocities, extending the range without requiring an increase in muzzle velocity.

That Mark VII sounds nasty - almost a dum-dum bullet by stealth. Were any concerns voiced about whether it was suitable ammo for gentlemen to shoot each other, or only to be used on "fuzzie-wuzzies"?

[neutrino]

I was told by someone who should know, that a sub machine gun bullet fired from a distance of 6 feet to 10 feet would not pass through a blanket held up losely in front of someone.

[Garron]

I would assume a SMG round would be the 9mm para, 6 to 10 feet is about 2-4 meters (give or take a few cm's), average smg effective range 25-50 meters (depending on the calibre)

Thats really doesnt make sense, a 9mm round can go throught a car door so a blanket would be no problem,

most pistol shooting ranges are 25m (could be yards) in the US (i think) and have paper targets, if a 9mm round can go through the paper target @ 25 meters a blanket at 2-4 meters should be easy.

i would recomend that he doesnt try this theory of his without proper armour, and a paramedic on standby

Cheers
Garron

[squirrel]

I have heard about this one as well, the blanket is suspended from a line but not fixed at the bottom, allegedly. The bloke who told me about it said it was part of a demonstration at the SASC at Warminster.

[Doug Johnson]

The Oak quoted would be fresh. Seriously aged Oak turns to a material similar to iron eg you can't even hammer a nail into it!

Helmets do not stop bullets. My father (WWII) had one go through his helmet and out again. Fortunately not low down enough to hit him. Unlike in the films, his helmet stayed on but he may have had it strapped on as he was a glider pilot. It was however painful to remove the helmet after as the rough edges of the in hole caught on his hair.

He could aslo have testified to the way bullets go through human flesh and the awful mess they make on exit!

Loose blankets have been demonstrated to be defensive as have curtains. They are the best defence against being cut to ribbons when the windows are shattered by a bomb. They absorb the impact of glass and most of it falls in a heap adjacent the window.

Doug

[Garron]

so a bullet can go through a a iron car but not a blanket thats suspended on a wire, thats some what confusing and hard to comprehend.

still really I wouldnt want to test that,

Garron

[IanA]

No sort of ballistics expert, but I can understand where this is coming from. Thin sheet steel on a car is fixed - it has no give. A loose blanet might absorb the force of a bullet - the looseness is the key. I do not put myself forward for testing this theory!

Ian

[ChrisC]

John.

The most graphic answer to this that I can give is...5.

(headshots with a Mauser Kar. 98 at point blank range into a row of adult males standing in single file almost touching each other - no details on a body shot).

Please don't ask me my source of this information - he is still alive and now enjoys a , well deserved, peaceable existance.

dave

I've only just come across this thread. This is reminiscent of a scene in Schindler's list where the SS is clearing the ghetto. I certainly agree that if your source was responsible for acts like that, he'd do well to keep quiet about it.

Chris C

[CROONAERT]

This is reminiscent of a scene in Schindler's list where the SS is clearing the ghetto. I certainly agree that if your source was responsible for acts like that, he'd do well to keep quiet about it.

Chris.

I didn't mention ghettos, nor did I mention that he had taken part in any of the acts of the type depicted in Schindler's List. He had witnessed such scenes, agreed, (as have many others) and has referred to events that might be regarded by some (by many) as attrocities but which, to him at the time were the accepted normality of his situation (and also pretty normal to his enemy too).

This man has suffered enormously in his life which is why I mention that he lives a "well deserved" peaceable existence nowadays. He doesn't have long left unfortunately. Some may say he will then finally pay in full for his actions (though i believe he has already done that tenfold), but I think that he will be truly happy again for the first time since 1941 when he rejoins his loved ones, all of whom he never saw again after that year.

He keeps quiet about his experiences to most because of the instant condemnation that he has recieved from many people. By your post, I think that you thought that way too?


Dave

[ChrisC]

Chris.

I didn't mention ghettos, nor did I mention that he had taken part in any of the acts of the type depicted in Schindler's List.
[b]No Dave I mentioned ghettos and the film because what you described was enacted there - 5 men in a row being shot with the weapon you described.

He had witnessed such scenes, agreed, (as have many others) and has referred to events that might be regarded by some (by many) as attrocities but which, to him at the time were the accepted normality of his situation (and also pretty normal to his enemy too).

The situation you described can only have been carried out on unarmed victims therefore it was nothing more nor less than murder. The fact that your contact's "enemies" did similar is beside the point.

This man has suffered enormously in his life which is why I mention that he lives a "well deserved" peaceable existence nowadays. He doesn't have long left unfortunately. Some may say he will then finally pay in full for his actions (though i believe he has already done that tenfold), but I think that he will be truly happy again for the first time since 1941 when he rejoins his loved ones, all of whom he never saw again after that year.

He keeps quiet about his experiences to most because of the instant condemnation that he has recieved from many people. By your post, I think that you thought that way too?
Dave

Yes Dave I do. I believe that to waste sympathy on the perpetrators of atrocities - no matter which side they were on is to demean the memory of the victim.

That's my opinion, matter closed so far as I am concerned.

Chris C