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Newbie "Guide" to gun literacy, calibers, acronyms etc.

Discussion in 'General Firearm Discussion' started by MissJ, Apr 15, 2011.

  1. MissJ

    MissJ Clackamas County Active Member

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    Hey all, I'm super interested in learning all that I can about guns, ammo, etc but sometimes in the midst of trying to learn I end up more confused. I want to learn more, but also am afraid of asking certain questions for fear of sounding like an idiot!:p

    Could we work on a "living" thread that attempts to give quick & dirty answers to commonly used acronyms and caliber references?

    One thing I would be particularly interested in knowing is a GENERAL ranking of ammunition sizes...I know that stopping power can vary greatly between the same "calibers" of ammunition depending on specifics...but just sort of a general list would be great.

    I'll start...and please feel free to correct me (as I'm sure that I'm wrong at least 40% of the time...)

    starting small to big:
    .17 (rifle)
    .22 (rifle or pistol)
    .223/5.56mm (rifle)
    .30/7.62 mm (rifle?...I could use some help here....this is a big topic I know)
    .38 special (pistol)
    .380/9mm (pistol)
    .40 (Pistol)
    .44 (pistol)
    .45 (pistol)
    .50 (pistol)
    20 gage (shotgun)
    12 gage (shotgun)

    I know this list is farm from perfect.

    I could really use some guidance in understanding where a .357 magnum and a .44 magnum fit in there. and what does it mean to be magnum anyways?

    and some terms that confuse me are:
    SKS (soviet assault rifle?)
    1911?
    ACP?
    lots more I'm forgetting I'm sure...
     
  2. WIRED tactical

    WIRED tactical Snohomish County, WA Member

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    We all start somewhere, so dont worry about sounding dumb. Let me go through the things I can answer well:

    .357 and .44 fit right in between .45 and .30 in terms of width. The caliber is the width of the round that is fired out of the barrel. It is measured in how much of an inch it is. For example a .50 cal is a half inch across. A .357 is .357th of a inch.

    1911 is the model number of the Browning 1911 pistol, produced in 1911. It is the name that almost all clones have given it since there and really is based on the original frame design.

    SKS is an acronym for Samozaryadnyj Karabin sistemy Simonova (Russian: Самозарядный карабин системы Симонова), 1945 (Self-loading Carbine of (the) Simonov system, 1945), or SKS 45. (from wikipedia) This is a type/model of Russian Rifle

    ACP in .45ACP stands for Automatic Cartidge Pistol. A name given by (browning?) when it developed the cartridge for the US.
     
  3. PhysicsGuy

    PhysicsGuy Corvallis, OR Resident Science Nut

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    One thing that you are confusing is "caliber" and "cartridge". Caliber is the diameter of the bullet, where as the cartridge usually refers to a specified type of ammunition. The "stopping power" is not directly dependent on the caliber. The design of the cartridge determines the case capacity and operating pressures, which determine (among other things) how fast it can propel the bullet down the barrel. The "stopping power" is greatly dependent on the kinetic energy the bullet has after it leaves the barrel, which is equal to the mass multiplied by the square of the velocity.

    Now that Ive gotten technical about it, I will simplify. An example would be ".45 caliber", this can refer to a many cartridges that use a 0.45" bullet, some handgun, and some rifle. These include; .45acp, .45 colt, .45gap, .45 S&W, .454 casull, .45-70 government, .458 winchester magnum, and the list goes on and on.

    For example, the following cartridges are all .45 caliber, but are very different;

    3x45.jpg
    (.45 acp, .45 colt, .45-70)
     
  4. MissJ

    MissJ Clackamas County Active Member

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    thanks, that was helpful!

    Also, synonyms would be great to point out. here's an example I just thought of:

    ammunition/cartridge/"chambered in"

    .38 can be fired in a .357 (why? I don't understand)
    but .357 cannot be fired in a .38 (again, I don't understand why?)

    .223 remigton and 5.56 mm NATO are interchangeable it seems?
     
  5. PhysicsGuy

    PhysicsGuy Corvallis, OR Resident Science Nut

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    One thing that I forgot to mention is that "caliber" is typically referring to the diameter in an inch system, but can also be used in metric. Typically when someone says .45 caliber (or 45 caliber), they are referring to a bullet that is approximately 0.45 inches in diameter. When used with metric, the caliber is almost always denoted with a mm following the number.

    Another thing on the topic of calibers/cartridges, one thing you have to keep an eye out for is that not all cartridges are actually the caliber that they appear to be. There are various reasons for this, but in modern day its usually for marketing purposes. For example a .45 acp sounds like its going to be approximately .45 caliber, and it is (.452"). But when you hear .454 casull or .460 S&W, you think they have a larger diameter bullet, but in reality, both cartridges use the same diameter bullet (.452").

    Other cartridges that are not actually the caliber they appear to be:
    .44 magnum and .44 special (.429 bullet)
    .38 special (.357 bullet)
    .357 sig (.355 bullet)
    .300 magnum (and any other ".300 or .30") use a .308 bullet
    ect

    And again, there are many various reasons for these discrepancies, some logical, others not. I wont get into too much detail about it, unless someone would really like to know
     
  6. Billy 4 HP

    Billy 4 HP Skagit Member

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    These are very legitimate and good questions, but also safety related that could really cause bodily harm and possibly worse if you don't fully grasp them properly or my information is false.

    Please don't take my words as being harsh, but like I said in your other thread, you really need to either make friends with a gun buddy that you trust your life with for some face to face Q&A time or ask / pay an old timer at your favorite gun shop that you trust to spend some time with you for a Q&A session. The internet is full of information, some good and some not so good.

    I personally wouldn't stake my life on information given on the internet and that's kinda what your getting yourself into. You don't know me from Adam, I am a new user on this forum with a low post count. I could be full of bull pucky or I might be a genius (yeah right).... :laugh:

    So to answer your questions in my words. A firearm chambered for .357 Magnum can fire .357 Magnum and both .38 special +P or regular old .38's as the physical measurements of both cartridges is negligible. A firearm chambered for .357 Magnum is designed to handle all the pressures created when the .357 Magnum cartridge is fired. But you CANNOT fire a .357 Magnum in a firearm chambered for .38 special +P or regular old .38's even though the case will likely fit because a .357 Magnum cartridge is loaded with more powder / faster burning powder which achieves a higher pressure resulting in a faster traveling projectile and more knock down power. A .38 has lower pressure, slower moving projectile, less knock down power. Firing a .357 Magnum cartridge in a firearm chambered .38 usually ends up with a destroyed firearm and bodily injury in short order, so as I am sure you have figured out a weapon chambered for .38 or .38 special +P is only designed to withstand the pressure of firing the .38 family cartridges.

    Aside from that, it's also good to check the barrel stamps on .38 special chambered firearm's to see if it's designed for standard .38 special only or the higher pressure .38 special +P cartridges...

    With .223 and 5.56 NATO it is the same basic story. You can fire a .223 in a firearm chambered for 5.56 NATO, but you shouldn't fire a 5.56 in a firearm chambered for .223. 5.56 NATO packs more punch and is actually a bit longer than an assembled .223, jamming a 5.56 into a firearm chambered in .223 can result in damage to the .223 chambered firearm in short order and or bodily harm to the end user...

    HTH and hang in there... I have seen first hand the results of a "newb" getting bad information and a face / arm full of shrapnel and if I can keep that from happening again to someone my work is done....
     
    Last edited: Apr 15, 2011
  7. PhysicsGuy

    PhysicsGuy Corvallis, OR Resident Science Nut

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    .38 special and .357 is one that always gets people. The reason the .38 special was named so is because it has a case neck diameter (diameter of case where the bullet sits) of 0.38", this convention was sometimes used "back in the day" instead of naming with the caliber of the bullet. In reality the .38 special uses a .357 caliber bullet.

    Now to explain the compatibility. The .357 magnum cartridge was designed from the .38 special to be a higher powered cartridge. It was strengthened to withstand higher pressures, allowing higher bullet velocities. The brass of the cartridge was made slightly longer than the .38 special to prevent people from firing .357 magnum in a .38 special. Because of the higher operating pressures of the .357 magnum, it would likely cause a gun built for .38 special pressures to explode.

    The reason you can fire .38 special out of .357 magnum guns is because it is essentially the same cartridge, just very slightly shorter, and lower pressure. Also this is possible because the cartridge "head-spaces" (where the cartridge is actually positioned by the chamber) on the rim, so the length of the cartridge does not matter for safe operation. Please note that this is NOT true for any cartridge that headspaces on the shoulder (bottlenecked rifle) or neck (most autoloading cartridges), so you cannot safely shoot lets say .380acp (9x17mm) in a 9mm auto (9x17mm)gun although the cases are similar but one is shorter (there are other differences between the cartridges too).

    Hope that helps!
     
  8. PhysicsGuy

    PhysicsGuy Corvallis, OR Resident Science Nut

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    Oh and as far as .223 remington and 5.56x45mm... This is a bit more tricky to explain, both cartridges are externally nearly identical in specifications. They both use the same bullet, and essentially the .223 remington is the commercial version of the cartridge, and 5.56 is the military's version. But there are differences in internal dimensions and other specifications that can actually give a substantial difference in ammunition produced.

    The safe interchangeability of these two cartridges has long been discussed and debated among gun enthusiasts and professionals alike. I'll leave it at the fact that 5.56 specifications can allow for higher pressures than .223. So many say that its only safe to shoot 5.56 in a 5.56 gun, others say its safe in either.
     
  9. MissJ

    MissJ Clackamas County Active Member

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    thanks, yes I find this very helpful indeed!
     
  10. blindfox

    blindfox tacoma, wa New Member

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    ballistics is an area of study that will yield great results in understanding the concepts behind a lot of the reasons bullets, barrels, actions, etc. are made. understanding the things going on during internal, external, and terminal ballistics will shed a lot of light on why things are the way they are with guns.

    some good books to read that discuss ballistics in practical detail are the ultimate sniper by john plaster and the army's sniper field manual FM 23-10. there are, of course a host of other books, but early in life these aided me greatly in learning a lot of the principles involved.

    and PG, i love it when you get technical ;)
     
  11. PhysicsGuy

    PhysicsGuy Corvallis, OR Resident Science Nut

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    Another thing that you might notice when looking at ammunition and/or firearms is the term "+p"... To give background; specifications of maximum cartridges pressures are defined by organizations such as SAAMI, and in recent times have come out with specifications for overpressure rounds commonly called "+p". These are the exact same cartridges just with essentially more powder, giving them a higher pressure. Some manufacturers design there modern firearms to be capable of handling these higher pressures (but usually advise against constantly shooting +P ammo). You definitely want to make sure that it is safe to use +p ammunition in a particular firearm before attempting to do so (typically stated in the manual). The appeal of this +P ammo is typically for self defense, where adding a little more velocity can increase stopping power.

    Another term that is (rarely) seen is +p+, which means it is any pressure above the (SAAMI) +p specifications, thereby no gun is actually designed to use this specification because it can be anywhere from 1psi more pressure to many many times more.

    And in case you were curious, SAAMI stands for "Sporting Arms and Ammunition Manufacturers' Institute"
     
  12. MissJ

    MissJ Clackamas County Active Member

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    thanks so much for your reply and concern, and it is well received!

    Personally speaking, I am currently involved in my local "gun community" to the point that I have been taking classes at the rifle range that is 6 miles from my house, and have been making friends with the retired, life long gun "buffs" and former military/police folk that frequent the club.

    I guess my concern stems from the fact that I feel, out of respect, I should do my "due diligence" on my own time to learn some of the basics of gun literacy so as to make the best use of everyone's time. I mean how would you like to sacrifice a few hours of your saturday to teach a girl how to fire a rifle, and then learn that she doesn't even know her A,B,Cs and you are supposed to teach her start to finish in 2 hours? I just feel it is respectful and efficient to do as much of my own research as possible; and then EVERYONE'S time is better spent.

    But your comments are appreciated and acknowledged as being sound advice that I intend to follow. I don't want any schrapnel in my pretty little mug!
     
  13. Billy 4 HP

    Billy 4 HP Skagit Member

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    Well your definetely the exception and not the norm and I commend you for that... I know it sounds funny but Wikipedia has a ton of firearm information that I have found to be relatively accurate. If your local library isn't ran by liberalville they also usually have some good general firearm books that make for decent reading...

    Your approach is logical and I am glad to see your getting your information from multiple sources. Compare what everyone has to say and draw your own conclusion. And as usual the only dumb question(s) are the ones nobody asks.

    Keep doing what your doing and soon you'll be the local gun expert... :thumbup:
     
  14. blindfox

    blindfox tacoma, wa New Member

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    neither do we ;)

    it's good to see someone interested in their own education as opposed to those who just want you to suddenly make them a steely-eyed killer armed with their newest gat in 3 easy steps or less.
     
  15. PhysicsGuy

    PhysicsGuy Corvallis, OR Resident Science Nut

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    Also one final (maybe) thing from me on cartridges that you may see out there is the metric designation such as 5.56x45mm, 7.62x39mm, 7.62x51mm, ect.

    This basically is giving the caliber (in mm) of the bullet, and the length of the case. Typically this refers to a unique "popular" cartridge, but you cant just measure a piece of brass and assume that it is that particular cartridge, but there really arent enough cartridges out there to have major confusion when identifying them.

    Another similar term that you may see is something like 7.62x54r, where the "r" is referring to a rimmed cartridge. Although that particular cartridge is probably the only one with that designation that you are likely to encounter in every day gun life.

    Something else to know is the confusions between naming of the same cartridge. Probably the most popular is the "9mm", which 99% of the time refers to 9x19mm, which some people call 9mm auto, 9mm luger, 9mm para (or parabellum), 9mm nato, ect. The one thing to know is that these are all the same cartridge. But dont get it confused with the .380 auto (9x17mm), which is sometimes called the 9mm short, and another similarly confusing cartridge is the 9mm Makarov (9x18mm), which looks very similar to the 9x19mm.

    I hope that doesn't confuse you too much, but just always be sure to know what you are buying/shooting, because a simple mistake can have bad consequences.

    Another random term when looking at nato/russian/soviet rifle calibers are the terms 7.62 soviet, 7.62 russian, and 7.62 NATO. For clarification, the 7.62 soviet is referring to the 7.62x39, the 7.62 russian is the 7.62x54r, and the 7.62 NATO is the 7.62x51
     
    MissJ and (deleted member) like this.
  16. PhysicsGuy

    PhysicsGuy Corvallis, OR Resident Science Nut

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    Thanks, technical speak is one thing Im good at ;)
     
  17. blindfox

    blindfox tacoma, wa New Member

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    i knew i had a problem when i started explaining to my ex-wife the problems with our relationship as they related to carbon build-up on the interior workings of the AR-15 ;)

    i love guns :)
     
  18. PhysicsGuy

    PhysicsGuy Corvallis, OR Resident Science Nut

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    Never be afraid to ask questions though MissJ. Some people are afraid of looking dumb by asking questions, but if you dont, then you wont know!

    Also another term to know, never call a magazine a clip, its one of my big pet peeves. There are differences between a magazine and a clip :p
     
  19. MissJ

    MissJ Clackamas County Active Member

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    haha! this is funny to me... I am reformed now...but until a year ago I called magazines "clips" then I took a class at the local range and they have a whole display case designated to this topic.....it has magazines "like TEEN, PEOPLE Etc." on one side. on the other side it has clips like "hair clips, chip clips, clothespins" etc. on the other side....they got VERY visual in their distinctions.....
     
  20. blindfox

    blindfox tacoma, wa New Member

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    MissJ, what kind of shooting do you enjoy? do you mostly shoot rifles from a benchrest? battlle-focus tactical stuff? trap or skeet?
    do you have a favorite firearm? why? do you carry concealed or not at all?
    are you interested in competition shooting?