Confused

Discussion in 'General Rifle Discussion' started by 45JMB, Mar 2, 2013.

  1. 45JMB

    45JMB New Member

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    I know that a M16 fires the 5.56x45 but AR15 fires the 5.56x39 right? Which is known as .223
     
  2. unclebear

    unclebear New Member

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    no, I don't know a whole lot about AR's but they there are some with a stamp that says 5.56X45 and some that say 223 really they pretty much the same round, They"re are some small differences in measurement just like 7.62X51 to 308.

    The AK rounds are 7.62X39 (AKM) and 5.45X39 (AK74)
     

  3. Apex-Predator

    Apex-Predator New Member

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    Yeah there is no 5.56x39, or if there is it is some funky wildcat cartridge.
     
  4. BULLET9992

    BULLET9992 New Member

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    The difference of the .223 & 5.56x45mm are negligible or even non existent. When the 556 was originally designed it may have had higher chamber pressure but with modern powder some 223 ammo out performs the 556. The difference is how it's measured. The .223 Remington has a .223 inch wide bullet, that's where it gets the name. The 556 has a 5.56mm wide bullet (same as .223") & a 45mm leangth casing. The 556 NATO is only different in the way that it is a metricly measured round & that's it. Allowing it to be a world wide recognised ammunition size & meeting NATO requirements. They'll both feed & fire properly out of either a 223 or 556 gun.
     
  5. BULLET9992

    BULLET9992 New Member

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    Unless it's military ammo, then the 556 ammunition may have higher chamber pressures. Typically for any specialty ammo.
     
  6. 45JMB

    45JMB New Member

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    Thanks a lot guys. It's just because people said that the .223 and 5.56.39 Are totally different rounds.
     
  7. Apex-Predator

    Apex-Predator New Member

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    5.56x45 IS different then 223, just not very different. They have the same outside dimensions but the thickness of the brass and pressure are different. Technically you are not supposed to fire 5.56x45 out of a 223 but you can fire 223 out of a 5.56x45 since the 5.56 is a higher pressure round.
     
  8. BULLET9992

    BULLET9992 New Member

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    Depends on what 556 you get. The vast majority have no differences. If I had to choose between a 223 ar & a mil spec 556. I'd go for the 556 even if it's a little more expensive. They're typically better made. In a bolt gun your set because they're designed for high pressure ammo.
     
  9. Jagermeister

    Jagermeister New Member

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    Mil Spec ammo runs pretty hot, so you shoot higher then say a hunting round. Not as good quality then hunting ammo. Also, I noticed that my .308 hunting round is slower but better quality and very accurate.. The NATO/mil spec shoots about 2.5 to 3 inches higher at 100 meters and grouping can be questionable per box. The mil ammo also makes the rifle barrel really dirty in a short period of time. The NATO rounds is a third of the price though. If you are using the gun for self defense and target shooting go with mil spec. I would not use "NATO" rounds for hunting or competition. I am also too lazy to continually adjust scope between ammo.
     
  10. mchoitz

    mchoitz New Member

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    It's not recommended to shoot 5.56 out of a .223 barrel but you can shoot a .223 out of a 5.56 barrel no problem
     
  11. Jagermeister

    Jagermeister New Member

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    Really, that statement made my day. Funny. I have seen a guy actually damage his gun that way. People believe certain myths about guns. Oh here is another one, I heard that a .45 will stop a man even if you shoot him in the ear. Anybody else have some myths about guns.
     
    Last edited: Mar 2, 2013
  12. BULLET9992

    BULLET9992 New Member

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    There is this crazy myth going around that they are inherently evil & have been known to kill themselves with no operator.
     
  13. Jpyle

    Jpyle New Member

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    The Remington .223 and NATO 5.56 x 45 are essentially the same round. There are differences that limit use of a 5.56 in a .223 chambered barrel but the case length is the same at 45 mm. 5.56 x 39 is not a typical AR round, you may be confusing it with the 7.62 x 39 round used in an AK-47 or the 5.45 x 39 used in the AK-74.
     
  14. Apex-Predator

    Apex-Predator New Member

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    Yep, my favorite is the one about how a 30-06 drops downrange and then comes back up again, but only 30-06s do it LMAO heard that one several times over the years.
    I had a debate with my boss about that one, I tried to explain to him that bullets don't come out of your scope, but he does not get it, and not he can't shoot.
     
  15. JWagner

    JWagner New Member

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  16. locutus

    locutus Well-Known Member Supporter

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    The .223 uses a .224 diameter bullet. Just like the 5.56X45.

    The 5.56 MM chamber has a longer leade to accommodate the longer special purpose rounds like tracer. The 5.56X45 cases have thicker walls and a heavier web to handle the increased pressure of the military round.

    5.56X45 is loaded to pressures well over 60K PSI. Commercial .223 Remington is loaded to no more than 55K PSI.

    No matter what someone on the internet tells you, DO NOT USE MILITARY 5.56X45 AMMO IN A COMMERCIAL .223 REMINGTON CHAMBER.

    There is a difference, and anyone who tells you otherwise does not know what the hell he's talking about!
     
  17. montveil

    montveil New Member

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    The 223 chamber is slightly shorter than the 5.56 and caused the 5.56 bullet to "jam in a 223 chamber causing higher and dangerous pressures.
    A 5.56 can fire a 223 but not the reverse.
    I got some Winchester frangible bullets ( they are made to powder upon impact) and fired them through my 223 and they just blew apart in the barrel causing nothing but powder to exit the barrel.
    I was a real wake up call for me as to what was happening and what might happen with a full metal jacket bullet.
     
  18. JTJ

    JTJ Well-Known Member Supporter

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    THERE IS NO 5.56X39!:eek:
    The NATO military cartridge is the 5.56x45.
     
  19. Apex-Predator

    Apex-Predator New Member

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    "The 223 chamber is slightly shorter than the 5.56 and caused the 5.56 bullet to "jam in a 223 chamber causing higher and dangerous pressures."

    Not true, 223 and 5.56 have the exact same SAAMI specs as far as external measurements go (just not pressure). If you are talking about the lands of the rifling that varies from rifle to rifle.
     
  20. jpattersonnh

    jpattersonnh Active Member

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    There is a difference, but upon weighing different 5.56x45 rounds, there really is not thicker brass, they would weigh more. The 5.56 chamber is a little more , here comes the bad word, Liberal, not quite as tight. One issue you may find on researching the pressure is that sammi uses 1 method, Nato another. As far as the leade, you are correct, but that is also to aleave pressure spikes.

    interesting, Winchester makes .223 frangable. Sure it was not the user??

    +1


    Even among manufacturers the 5.56, or Wylde can have many variances as far as chamber cuts.