Reverse bullet legend

Discussion in 'General Military Arms & History Forum' started by TranterUK, Jun 19, 2009.

  1. TranterUK

    TranterUK Guest

    Thought this may interest some,

    The reverse bullet legend comes from WW1. In short it went that the Germans, faced with the first Tanks, invented by the Brits discovered that their 7.92 rifle bullets bounced off the steel plate. But if they reversed the bullet in the case, so it flew backwards it would penetrate the steel. I knew of the story but few believed it, and certainly not me.

    Well I recently saw this tried out on a documentary, and guess what? It worked! a hole in the steel plate was formed with fragmentation of the plate thrown out behind. The bullet disintegrated.

    Strange, but as it turned out, true.
  2. 45nut

    45nut Active Member

    Joined:
    Jul 19, 2006
    Messages:
    3,455
    Location:
    Dallas, TX
    :eek::eek::eek::eek:

    That is weird.
  3. Lotsdragon

    Lotsdragon New Member

    Joined:
    Apr 5, 2009
    Messages:
    813
    Location:
    Potosi, Mo
    LOL well that is a horse of another color!
  4. olmossbak

    olmossbak New Member

    Joined:
    Feb 12, 2009
    Messages:
    212
    Location:
    NE Tenn
    What about the spent cobalt 7,62 bullets supplied to the Afgans to use against the Russians? Are you familiar with that story?
  5. TranterUK

    TranterUK Guest

    What do you know?
  6. Interesting, Tranter. It surprises me that a bullet without an ogive could penetrate steel. On the other hand, shaped charges work somewhat on that principle, the idea being for the projectile to burn its way through the material it impacts creating spawl.
  7. Suwannee Tim

    Suwannee Tim New Member

    Joined:
    Feb 11, 2009
    Messages:
    2,227
    That sounds like spalling where a chip files off the inside of the armor. HESH, high explosive squash head shells are designed to do this. Shaped charges are different, they melt a hole through the armor.
  8. 308 at my gate

    308 at my gate New Member

    Joined:
    Dec 6, 2008
    Messages:
    847
    Location:
    Lost in SW USA.
    I would have to see it to believe.
  9. olmossbak

    olmossbak New Member

    Joined:
    Feb 12, 2009
    Messages:
    212
    Location:
    NE Tenn
    I know nothing, just something I heard somewhere.
  10. olmossbak

    olmossbak New Member

    Joined:
    Feb 12, 2009
    Messages:
    212
    Location:
    NE Tenn
    Shaped charges detonate, or rather burn, a set distance from the armor and the copper jet created burns through the armor. That is why stand-off armor works against the RPG7, etc. It is the grating you see on the Strikers, aka armored Renaults.
  11. TranterUK

    TranterUK Guest

    I can tell you what I saw. Much to the surprise of the Army guys running the test, who doubted it would work and said so, a large hole was made in the steel plate, with peppering from impact behind.

    It occurs to me that like a small shaped charge the base of the bullet may have been concave, I dont know, but a large hole was made.

    I for one found this fascinating. If you reverse a .30 bullet in its case and fire it at plate steel, it seems it will make a hole, where it would not when fired point first. An old story that seems to be factual.
    Last edited by a moderator: Jun 20, 2009
  12. kutaho

    kutaho New Member

    Joined:
    Apr 15, 2009
    Messages:
    1,851
    Location:
    Peoples Republic of the Pacific Northwest
    Good logic:)
  13. It does make sense if you think about it, Tranter. Perhaps you remember reading about the steel plates the Germans used in WWI to protect their snipers sent out into No Man's Land to shoot at British troops. For some time the British could do relatively little about them since the .303s they were using simply would not penetrate the steel. Someone got the bright idea to send out a call to the civilian population for some African caliber double rifles, calibers such as the .577 and .600 Nitro Express. It turned out that those heavy, blunt-nosed bullets made short work of the German steel! I've seen photos of the German steel protective plates with nice, neat half-inch or better holes drilled right through them, and doubtless the sniper behind the steel! ;)
  14. TranterUK

    TranterUK Guest

    Perhaps we should get mythbusters on it?
  15. I think they much prefer to just blow things up, Tranter, not make neat holes in it. :D Perhaps if we suggested they place about five lbs of C4 behind the steel plate it would interest them more. :eek::D
  16. delta13soultaker

    delta13soultaker New Member

    Joined:
    Dec 26, 2003
    Messages:
    2,948
    Location:
    Depends on Uncle Sam's whim every 3 yrs.
    Tranter, from my understanding of the mechanics of metal/steel/alloy armor penetration.....

    The explanation is simply that backwards, the bullet fails and flattens on the plate, transferring all its energy into one point and spalling the back.

    That was actually a primitive method of AP ammunition production....they made bullets that were designed to flatten on the armor and spall the other side. A conventional bullet just bounces off.

    *This is totally opposite of the heavy metal penetrator method; although both kinetic, different method, with a heavy metal penetrator being drastically more efficient and with more effect on what's behind the armor.

    **This is absolutely nothing like how a shaped charge penetrates armor. A HEAT projectile uses chemical penetration as opposed to kinetic force. HEAT is less efficient than heavy metal penetrators, but in low velocity weapons it is the only realistic method.


    So here is your answer though...the bullet flattens on the plate and the instant energy transfer spalls the back. (This is one of several principles you learn while learning to engineer, teach, and build improvised munitions.)
  17. nightfighter

    nightfighter New Member

    Joined:
    Feb 28, 2007
    Messages:
    118
    Spent cobalt???
  18. Millwright

    Millwright Active Member

    Joined:
    Jun 30, 2005
    Messages:
    1,759
    Nice tale, Tranter !!

    Re the "tests"; what was the "grazing angle" of bullets penetrating the "armour" ? (We'll leave out of discussion the type of steel used in the target FTTB.) On a near 90' angle the base-first bullet would have a lot more "bite" into the steel, consequently better energy transfer resulting in spalling or holing of the plate.

    Nose first, a cupro-nickel jacketed bullet spinning at 100K rpm would likely fragment from to nose back due to the torsional stresses set up on impact. I recall the Germans settled for a monster 12mm Mauser-pattern bolt rifle as an anti-tank weapon. It wasn't popular with the troops assigned to tote it....

    Many years' back we did an impromptu test at the farm. The target was a 5/8" MS steel plate at 150 yds. The cartridges were a 7mm Rem Mag at around 140 gr vs a .35 Rem with around 165 gr. "Corlokts" as I recall. The 7 mm had no problem penetrating mild steel. The .35 dimpled it. When we "examined the evidence", I noted star patterns of copper on the front side, which leads me to conclude the nose of the bullet "broke up" and only the base penetrated. The .35 produced a shiny copper-plated divot in the steel.

    Trouble with any of these "comparisons" is establishing a base line. Early mass-produced steel was inconsistent in hardness and tensile strength. Witness later discoveries about the Titanic. >MW
  19. USMC-03

    USMC-03 New Member

    Joined:
    Oct 17, 2007
    Messages:
    1,825
    Location:
    Peoples Republic of the Pacific Northwest
    It seems to be much the same principle as used to make round holes in plate steel with a punch press. I would also make the assumption that in combination with this principle, the bullet would also have to strike the armor plate at an almost perfect perpendicular angle. Great practical science...
  20. delta13soultaker

    delta13soultaker New Member

    Joined:
    Dec 26, 2003
    Messages:
    2,948
    Location:
    Depends on Uncle Sam's whim every 3 yrs.
    Yup. It was primitive and obsolete fairly quick. Sloped armor wasn't yet very common, except by coincidence.
Similar Threads
Forum Title Date
General Military Arms & History Forum No hiding place from new U.S. Army rifles that use radio-controlled smart bullets Feb 9, 2011
General Military Arms & History Forum JACKETED BULLETS / SMOKELESS POWDER a topic of merit Apr 22, 2006
General Military Arms & History Forum Stash247, re: small bullets / rate of fire Dec 13, 2004