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Shooting locks

  1. Mar 3, 2008 #1


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    To gain entry, myth busters showed that one would need armour piercing bullets to wreck a pad lock, and that one may be showered in shrapnel in the process, so are any of the shooting locks movies possible?
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  3. Mar 3, 2008 #2


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    It all basically depends on what gun you're using and what kind of lock is being shot. Needless to say, it's difficult to get a lead bullet to pass through a hardened steel lock.

    The Mythbusters episode basically showed that you would need a powerful rifle or shotgun with a slug in it to bust a door's deadbolt; it essentially blows the entire lock assembly out of the door. I don't remember if they also shot padlocks, but I suspect the result would be similar, I don't think a handgun's round carries enough energy to blow through a strong lock.
  4. Mar 3, 2008 #3


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    IIRC, Master Lock used to use this in a commercial. Their locks can withstand a bullet, though like ME said, it depends on the bullet/gun and lock.
  5. Mar 3, 2008 #4


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    Here it is:
    [I wasn't alive to watch that Super Bowl....]
  6. Mar 12, 2008 #5
  7. Mar 12, 2008 #6


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    That's why standard procedure for the boys in blue (or green) is to shoot the hinges off the other side with shotguns.
  8. Mar 14, 2008 #7
    I watched my son kick a padlock off. He flipped it up so the back side was exposed, and with about 4 good kicks it sort of fell apart. I asked where he learned that trick, he said he learned back in high school from some guy that took karate classes.
  9. Mar 14, 2008 #8


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    http://www.theboxotruth.com/docs/bot5.htm" [Broken] is a guy experiment and his documented results.

    (Summary: Not with any hand gun or rifles, but yes with a shotgun slug.)
    Last edited by a moderator: May 3, 2017
  10. Apr 1, 2008 #9
    There are actually special rounds one can use specifically for taking the hinges off a door. Which is just as effective as taking the lock off in terms of getting the door open. Specifically, hardened ceramic balls loaded in shotgun shells blow the hinges apart but disintegrate themselves reducing richochet and shrapnel.
  11. Apr 1, 2008 #10
    Depends on the lock. Assuming it's a master lock, I'm sure those can take on a wide array of bullets.

    However, I am not sure if it can withstand a 50 caliber bullet (never tried it myself, nor do I know anyone with a 50 caliber firearm). 50 caliber bullets were used to take down aircrafts as well as tanks, so I'm sure it can destroy a Masterlock. There ARE 50 caliber handguns http://en.wikipedia.org/wiki/.50_caliber_handguns.

    Now it'd be cool if someone can test this, but I'm not sure about how the lock would explode. I'm not responsible if anyone gets hurt doing this ;-p
  12. Apr 14, 2008 #11
    I'm sure it could if you have a big enough gun
  13. Apr 29, 2008 #12


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    As a locksmith, I don't doubt for a moment the Master padlock's ability to withstand a .44 Magnum round (that's what the print adds used). Those bodies are laminated steel plates riveted together with a couple of tonnes of pressure. The rivets expand into the holes in each plate, not just on the top and bottom. I tried to take one apart with a 5lb. hammer and cold chisel once and couldn't even get its attention.
  14. May 14, 2008 #13
    Has anyone tried shooting the lock at the spot where the key is inserted? Not sure if that steel (the part where the key goes) is hardened or not.

    just a thought.
  15. May 31, 2008 #14
    I saw this episode, and I was supprised it took so much force to break the lock, it looks so easy in movies.
  16. Jun 3, 2008 #15
    My few cents worth...

    I believe I can add some valuable insight to this discussion...

    My father and I have always been deeply involved in the shooting sports, and he happened to be involved in the contracting of the well-remembered Master Lock commercial discussed here.

    All of these 'what about X' comments are kind of missing the essence of the matter--- each of the apparently conflicting statements are true. It IS possible to kick a lock apart with your foot, AND it's possible to have bullets 'bounce off' of one... It's all a question of the energy involved, and how it's applied to the lock.

    So, whatever it is you hope the lock will do, you merely have to apply the right force to cause that effect.

    In the case of the Master commercial, they wanted what you saw in the final TV edit--- a nice, clean hole right through the lock, with the lock staying locked. What they actually got on the first try (using an elephant rifle with standard jacketed bullets) was a lock so completely blasted apart they couldn't even find any parts of it, excepting the shackle of the lock (which was horribly bent but still on the metal staple).

    To get the effect shown on TV, they switched to a different choice of firearm and cartridge (for higher velocity), and used armor-piercing bullets (I seem to remember it was a .300 Winchester Magnum, but don't quote me on that; certainly one of the 'belted magnum' rifle calibers). This gave them the nice clean hole they were looking for, without delivering enough energy to destroy the lock.

    Incidentally, there was also an inset photo in some of the print ads which 'showed' that it had taken 16 shots of this type to actually open the lock--- overall, both presentations implied that a Master padlock couldn't be shot open with a gun. In point of fact, some of the more wildcat handgun cartridges could probably do it; as long as they delivered enough energy. It has to go somewhere, after all...

    In the commercial, most of that energy went right out the back of the lock, along with the bullet. On that first, lock-destroying attempt, just about every last foot-pound was delivered directly into the lock body, with predictable results.

    Someone mentioned the .50 AE (Action Express) handgun cartridge-- it should be noted that this is not an excessively-powerful handgun cartridge (at 1,250 ft·lbf), not as powerful as the .454 Casull (1,923 ft·lbf), for example, and certainly nothing like the .50 BMG machine-gun cartridge. Just because they both have a diameter of .5 inches doesn't imply any other equivalence--- so that statement about "shooting down airplanes" with a .50 AE is pretty silly. The .50 BMG, on the other hand, has MORE than enough energy to destroy these locks--- as much as 14,895 ft·lbf, with an 800-grain bullet. But the .50 BMG sniper rifles weren't really around yet when that commercial was made.

    Having fired an elephant rifle myself (in .470 Nitro Express), I can assure you it's an incredible amount of energy these rounds offer--- in the case of that particular caliber, 5,140 ft·lbf or 6,970 J of energy. I think it's clear, if you think about it, that this kind of energy simply MUST destroy the lock if it's effectively delivered. To turn things around a little, just consider how that kind of blunt force could be applied to a little piece of steel and NOT do significant work on it...

    Just to advance the discussion...
  17. Jun 3, 2008 #16
    Oh, yeah...

    By the way... if you all haven't noticed yet, the MythBusters guys are really not all that knowledgable about guns. I know they try, and God bless them (I do like them plenty, myself); but I guess this is what you get living in the People's Republic of California.

    If you doubt it, watch the episode involving bullets fired into water--- these two were AMAZED that water stops bullets so quickly... But five minutes at the local creek with a .22 will illustrate the same principle-- I remember learning exactly that at 8 years old, having found it's nearly impossible to shoot fish this way, even when they seem very close to the surface.

    I've often found that MythBusters "findings" are quite limited or constrained (in accuracy or depth) by the assumptions, knowledge, or experience (or lack of these) possessed by the testers.
  18. Jun 7, 2008 #17
    Referring to KTC's link, which I can't quote yet cause of forum regulations:

    After seeing this, I just can't help but wonder why people shoot the bodies of the lock, and not the hinge? Shouldn't the hinge be easier to break compared to the bodies, which can be reinforced with steel rivets, thousands of pounds of pressure, etc etc...

    My two cents.
  19. Jun 7, 2008 #18


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    Yes law enforcement shoot the hinges, this also avoids the chance of deadbolts etc on the lock side.
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