Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Liars, or merely ignorant?

  1. Jan 12, 2010 #1
    By coincidence I happen to currently know two separate guys who were, or claim to have been, snipers in the military. I never even thought to question their claims until the issue of bullet caliber came up.

    At the cafe where I hang out what is meant by bullet caliber was raised during a conversation. I was pretty sure, though not certain, it was a measurement of diameter, but someone else disputed that. It occurred to me the ex-sniper who hangs out there should be able to settle it, so I went and asked him. His hesitant answer was that he was fairly sure caliber was a measurement of bullet length.

    When I got home I consulted the wikipedia and found he was wrong.

    A few days later I started telling this story to the other ex-sniper I happen to know at a different cafe, and before I'd finished the story he interrupted me to say that caliber was a measure of bullet length.

    Caliber, is, in fact, a measurement of bullet diameter: both "snipers" were wrong.

    Of course one needn't know what caliber means to be a good enough shot to be a sniper, but it strikes me that this is a little too basic for an authentic sniper to be ignorant about.

    They're both nice guys, and don't speak of their military past with any particularly boastful tone, so I wonder how much weight I should give this gap in knowledge.
     
  2. jcsd
  3. Jan 12, 2010 #2

    turbo

    User Avatar
    Gold Member

    Caliber is a measure of the bullet's diameter. Throughout the post-WWII period and through Viet-Nam, the preferred caliber was .30. Specifically, .30-06, which refers not only to the .30 caliber, but the case-length and powder charge that was accepted by the US military in 1906. This is a very powerful and accurate round that is not only still highly regarded by the military, but is still used in target competition at many ranges.
     
    Last edited: Jan 12, 2010
  4. Jan 12, 2010 #3

    turbo

    User Avatar
    Gold Member

    I should add that during the VN war, it was decided that the military should standardize on .308. That was a .30 caliber round, but the cartridge was significantly shorter than that of a .30-06, which meant that an automatic or semi-automatic rifle's action could recycle much faster. The M14 was very popular. As soon as vast numbers of US soldiers started heading to VN, the production of .223 rifles blasted off.
     
  5. Jan 12, 2010 #4

    turbo

    User Avatar
    Gold Member

    During the Viet-Nam war, Marine snipers still used the .30-06 bolt-action rifles. Scoped rifles from that conflict can get huge prices from collectors. The best Springfield barrels on these bolt action rifles were marked with a stamped asterisk on the front surface of the barrel's face. If you use this information to find a sharp-shooter's rifle, PM me. There are very few collectors that appreciate the differences, but they are very well-heeled.
     
  6. Jan 12, 2010 #5
    Now we my be getting somewhere. My Marine Viet Nam era sniper claimed he used a version of the M-16, not a .30-06.

    Are you absolutely sure Marine Snipers in Viet Nam only used the .30-06?
     
  7. Jan 12, 2010 #6

    jacksonpeeble

    User Avatar
    Gold Member

    Now, I'm just playing devil's advocate here, and I'm no military expert; I know you're skeptical of these guys, but remember - you said that they claim to be "snipers in the military," not "snipers in the marines." They could use two different weapons.

    Caliber does seem like a basic concept to know, but it's hard to determine exactly what was taught to snipers back then; as mentioned, it's not essential knowledge.

    I would recommend asking a different question that they should definitely know; I agree with your skepticism. For example, if they DO say that they were marines AND the gun mentioned above WAS the only sniping gun used, ask what caliber their weapons were. Or figure something else out.
     
  8. Jan 12, 2010 #7
    I am actually asking if it's reasonable to be skeptical. Why should the military clutter anyone's mind with info that isn't directly necessary to the job? On the other hand, if you live by the gun wouldn't it be strange not to pick that kind of basic information up as a matter of course?

    One guy specifically claims to have been a Marine sniper in Viet Nam and he specifically said he used a version of the M-16. The other specifically claims to have been a sniper with the Navy Seals. He joined just after we officially pulled out of Viet Nam, but says he got sent to southeast asia anyway, that there was a certain amount of unofficial action going on, in conjunction with trying to get US prisoners out by hook or crook. He never mentioned what gun he used, and I never asked.
     
  9. Jan 12, 2010 #8

    turbo

    User Avatar
    Gold Member

    I cannot claim with any certainty that Marine snipers ONLY used Springfield .30-06 rifles. That is the gold standard for training snipers, though. I would be quite surprised to find that Marine snipers used any variant of the M16. That particular firearm is built around a cartridge that does not have a lot of power at long range, and is not particularly accurate at such.
     
  10. Jan 12, 2010 #9

    cronxeh

    User Avatar
    Gold Member

    A higher caliber bullet has a longer length, maybe that was the source of their misconception. To test their basic sniper knowledge you should ask them if you were to drop a bullet at the same time they shot it from a rifle - which bullet would hit the ground first

    From same wiki you referred to: "The bore to barrel length ratio is called caliber in naval gunnery, but is called length in army artillery"
     
  11. Jan 12, 2010 #10
    It so happens that snipper's bullets always have length equal to their circumference. So changing caliber causes the length to increase more three times more than the diameter, and the change in caliber results in a change in length more than three times more noticeable than the change in diameter.

    Seriously though, is not length linearly correlated with diameter, at least at first order ?

    wikipedia
    So maybe not only they are ignorant liars, but maybe they are also conspiring by changing wikipedia !
     
  12. Jan 12, 2010 #11
    Well, a trip to the wiki article on the M-16 reveals there was an M-16 sniper "variant":

    http://en.wikipedia.org/wiki/M16_rifle#Colt_Model_655_and_656_.22Sniper.22_variants
     
  13. Jan 12, 2010 #12
  14. Jan 12, 2010 #13
    Liars
     
  15. Jan 12, 2010 #14

    turbo

    User Avatar
    Gold Member

    Zoob, there is NO way that any Marine sniper could be ignorant of the caliber of rifle that they used in the war. Not possible. I hunt with large-caliber rounds for stopping power. Marines would demand enough stopping power ti do at least as well at long ranges.
     
  16. Jan 12, 2010 #15
    That's measure of the bore of the weapon however, not the bullet. So the snipers would still have been wrong. However I would not doubt them if they say that they were in the vietnam war as snipers. The Americans in the vietnam war were young and enlisted I would say mostly out of 'patriotism'. I would doubt that a description of what calibre meant would have come up during training at this time. They wanted... and needed... to get more soldiers to go over and stay over fighting quick. They may have been like 'such and such weapon uses these bullets, this is how you reload this is how you maintain' etc. but probably never described what the terms meant.

    In order to become a sniper at this time you probably just needed to be a good marksman.
     
  17. Jan 12, 2010 #16

    turbo

    User Avatar
    Gold Member

    mis-typed "03 vs 06"
     
  18. Jan 12, 2010 #17

    DaveC426913

    User Avatar
    Gold Member

    This is of little help in this thread but the above made me think of a thread from years ago in which the discussion revolved around the follow-through of a martial punch.

    It became apparent that what martial arts students were being taught about packing energy into the follow-through was actually pseudo-mystical nonsense in the guise of physics theory.
     
  19. Jan 12, 2010 #18
    I don't agree with this statement at all.
    Firstly:
    No one said they were ignorant of anything to do with their gun they just don't know what calibre MEANS, that has nothing to do with if they know what calibre of bullet their gun would use.

    Secondly:
    These are not modern day marines we're talking about here. More than likely the top marksmen all became snipers at this time and were given a suitible rifle for them to use. I don't see why them using higher calibre bullets would imply they NEED to understand what calibre means.
     
  20. Jan 12, 2010 #19
    That is probably it. However, the reason I suspected caliber was a measure of diameter in the first place was a recollection from childhood (over hearing the conversations of relatives who hunted) that one can buy bullets of the same caliber but of different lengths for different purposes. Knowing that, it's easy to reason out that the non-changing dimension must be the diameter. That's why I checked the wikipedia after the first one claimed "length". Didn't make sense.
    I might try that if I can work it in without sounding like I'm suspicious of their story.
    Yeah, I saw that, too, but there's no reason for them to know that system much less confuse it with bullet caliber.
     
  21. Jan 12, 2010 #20
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook