shooting 308 in 7.62x51 rifle

Discussion in 'General Rifle Discussion' started by Armed-Citizen, Oct 30, 2012.

  1. Armed-Citizen

    Armed-Citizen New Member

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    can you shoot 308 through a rifle made for 7.62x51?
    I'm thinking of picking up a lee enfield ishpore 2a1 chambered in 7.62x51 and was wanting to know if it can use commercial 308 rounds?
    has anyone tried it?
    thanks in advance
     
  2. hiwall

    hiwall Well-Known Member

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    it is the same cartridge
     

  3. c3shooter

    c3shooter Administrator Staff Member

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    If you mean 7.62 NATO and .308 Winchester, no- theyare not the same. External dimensions SIMILAR, internal NOT the same, load pressures not the same. You can shoot 7.62 NATO in a .308 safely, but the opposite is not always true. The Ishapore should not fire .308 Winchester.
     
  4. Yunus

    Yunus New Member

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    Something I have learned after years of reading this board.

    If you are buying a .308 or 7.62X51 you want the .308 stamped barrel.

    If you are buying a .223 or 5.56 you want the 5.56 stamped barrel.

    Many threads go into details about why but that is what they all boil down to for those of us looking to shoot the cheapest ammo you can find.
     
  5. JonM

    JonM Moderator

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    the only loading in 308 winchester that is safe in a 7.62nato chamber are ones loaded to 2700fps in a 20" barrel with a 147grain fmj bullet using ball powder. anything else is too high pressured for a 7.62 nato chamber.

    its just the opposite of 556 and 223.
     
  6. 303tom

    303tom Well-Known Member

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    Sorry, but I shoot .308 Win. in my Enfield 2A1 all the time...............
     
  7. jpattersonnh

    jpattersonnh Active Member

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    Tom, It will over time damage the bolt/action. Can it be done, sure. Should it be? That is up to the shooter.
     
  8. mountainman13

    mountainman13 New Member

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    I've heard this argument with 5.56 also. People say you can shoot 5.56 in a .223 bolt action. I say I have no desire to have a bolt shot into my face.
     
  9. SSGN_Doc

    SSGN_Doc Well-Known Member

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    In bolt guns it is usually not as big of a deal. I say usually because not all bolt guns are built the same. One issue with the Enfield design is the rear bolt lugs. When compared to rifles with forward bolt lugs it is less tolerant of higher pressures.

    Me personally. I wouldn't do it. But I can handload a safe hunting round for it.
     
  10. gunnut07

    gunnut07 New Member

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    You are talking about 60,200 PSI for 7.62 to 62,000 psi for 308 win. 1800PSI difference isn't going to make any difference.
     
  11. 303tom

    303tom Well-Known Member

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    .223/5.56...........
    According to the official Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives (C.I.P.) guidelines the .223 Remington case can handle up to 430 megapascals (62,366 psi) piezo pressure. In C.I.P. regulated countries every rifle cartridge combo has to be proofed at 125% of this maximum C.I.P. pressure to certify for sale to consumers. This is equal to the NATO maximum service pressure guideline for the 5.56x45mm NATO cartridge.

    According to the official NATO proofing guidelines the 5.56×45mm NATO case can handle up to 430 MPa (62,000 psi) piezo service pressure. In NATO regulated organizations every rifle cartridge combo has to be proofed at 125% of this maximum pressure to certify for service issue. This is equal to the C.I.P. maximum pressure guideline for the .223 Remington cartridge, that is the 5.56×45mm NATO parent cartridge.

    .308.7.62............
    Although not identical, the 7.62×51mm NATO and the commercial .308 Winchester cartridges are similar, and even though the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI) considers it safe (by not listing it) to fire the NATO round in weapons chambered for the commercial round, there is significant discussion about compatible chamber and muzzle pressures between the two cartridges based on powder loads and wall thicknesses on the military vs. commercial rounds.

    According to the official C.I.P. (Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives) guidelines the .308 Winchester case can handle up to 415 MPa (60,190 psi) piezo pressure. In C.I.P. regulated countries every rifle cartridge combo has to be proofed at 125% of this maximum C.I.P. pressure to certify for sale to consumers...............
     
  12. JTJ

    JTJ Well-Known Member Supporter

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    The problem in the 223 chambered rifles is the throat. It is longer in the 5.56. While it is only a 10% overload which is easily handled by most actions the shorter throat can cause a pressure surge to 30% or higher especially with the heavier bullets. Now as to the 308, I have fired surplus 7.62x51 in a 308 and had heavier recoil and mild signs of high pressure. The NATO round was hotter than the 308. I believe it was South African. I have never had an opportunity to fire 308 in a NATO chambered rifle.
     
  13. JonM

    JonM Moderator

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    The difference is in throating. 556 and 308win have longer throats than 223 and 762nato have shorter throats. When you load longer profile bullets into those chambers the pressure jumps radically to dangerous levels. The 762nato is chambered to use a 147grain bullet when you use larger ones in the 175grain and up the ogive can touch the lands. Thats why you dont use 308win in a nato chamber.
     
  14. Yunus

    Yunus New Member

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    If I am not mistaken I believe another difference is the method used to measure pressure is different for the american specs (.223, .308) than for the european specs (5.56, 7.62). This means the numbers are not an apples to apples comparison.
     
  15. Threetango

    Threetango Audentes Fortuna Iuvat Supporter

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    I've had no problem shooting both 308 and 7.62X51 in my Bushmaster MOE 308 and according to Bushmaster it's fine.
     
  16. gunnut07

    gunnut07 New Member

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    Pressure in psi (Pounds per Square Inch) is the same no matter who measures it. Now if one were cup and one psi then yes. There is no formula to derive one from the other.

    CUP = Copper Units of Pressure.
     
  17. jpattersonnh

    jpattersonnh Active Member

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    The man has a point! The fomulas that try to change CUP to PSI, or visa versa just don't work.
     
  18. Yunus

    Yunus New Member

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    WHO is not relevant to the measurement but WHERE is a very important factor.

    http://guncentral.net/Articles/SAAMIvsNATO.html
     
  19. cottontop

    cottontop Guest

    I don't worry about it any more. I sold my .308 and bought a Remington Model 722 bolt action in .300 Savage. I love the older cartridges that everyone at the range does not have. I get sub-moa accuracy from this old rifle at near .308 velocities. I make brass for it from .308 brass, and it is very easy to do. Just an old fart having fun.
    cottontop