Does ANYONE reload 7.62 Nato Milspec ammo???

Discussion in 'Ammunition & Reloading' started by capnklump, Sep 3, 2012.

  1. capnklump

    capnklump New Member

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    Just was reading in Springfields M1A manual, & it said any ammo other than FACTORY 7.62 milspec voids the warranty. I know you cant use 308 win due to the pressure & headspace issues, so what gives? Does anyone reload 7.62X51 Nato??
     
  2. robocop10mm

    robocop10mm Lifetime Supporting Member Lifetime Supporter

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    I load .308 brass and 7.62 NATO brass about 2 full grains under max for my HK, CETME and FR-8.
     

  3. 25-5

    25-5 New Member

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    The mil. manual you get is for M14. The barrel is stamped .308. As stated light load. I load 168 gr Horady A-Max w/ 42 gr Varget. Going to try 43 gr.
     
  4. capnklump

    capnklump New Member

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    Let me know how the 43 gr works out.
     
  5. c3shooter

    c3shooter Administrator Staff Member

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    Pretty much a standard disclaimer by MANY gun makers.
     
  6. steve4102

    steve4102 New Member

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    The 308 and the 7.62 are loaded to nearly identical pressures.

    It is a myth. The 7.62 Nato round runs at the same pressure as the 308 Win.

    The pressure in the .308 and the 7.62 virtually identical. The 308 runs at 62Kpsi the 7.62 Nato runs at 50K CUP not psi which equates to about 62K psi. The 7.62 was never testing in psi it was tested in CUP and some dumb ass in the US Military exchanged the CUP for PSI in an official document and has cauised mass confusion ever since.

    If you look through military ammo specs from before the mid-90's, you find military copper crusher numbers reported as "psi" at the same time a commercial maker would have reported them as "CUP" (I don't know why "CUP" gets caps while "psi" gets lower case, but that's how SAAMI publishes them). The SAAMI conformal piezo spec is 62,000 psi MAP (Maximum Average Pressure). I'll have to check, but I recall SAAMI MAP allows up to 4% deviation from average, so 64,480 psi would be the allowed extreme spread in SAAMI compliant ammo.

    The NATO allies use 415 MPa, which the CIP uses for both 7.62 NATO and .308 Winchester. That converts to 60,191 psi, but the CIP measuring system sets the sample point further forward in the case, so it sees a bit of the pressure drop at the bullet base that occurs when the bullet starts moving. That makes them tend to read about 2,000 psi lower than the SAAMI setup does in this pressure range. So the same ammo would measure closer to 62,000 psi in SAAMI equipment.

    http://www.ar15.com/media/mediaFiles/348/32231.JPG

    Now take the load data from the document above (172gr bullet, 44gr IMR-4895) and compare it to some 308 Win data in your loading manuals. You will see that there is no way that this load of 44gr IMR-4895 can be running at 50K PSI. It is Running at 60K PSI or 50K CUP.


    You can also go to Midway and check out their ammo. Note the Federal 7.62 ammo has identical ballistics, fps, fpe as the same load in 308 Win. Only way these two can have the same ballistics is if they are running at the exact same pressure.
    http://www.midwayusa.com/product/95...nition-762x51mm-nato-168-grain-open-tip-match

    http://www.midwayusa.com/product/95...grain-sierra-matchking-hollow-point-boat-tail
     
  7. jpattersonnh

    jpattersonnh Active Member

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    Steve, I'll let you shoot a box of 7.62x51 w/ a mix of Israeli, Portuguese, and German ammo. Then you shoot a box of 150gr commercial. You tell me if there is a difference in the functioning of the firearm. Believing what a manufacturer/ seller publishes is like believing the Dems, it is always on the high side.
     
  8. steve4102

    steve4102 New Member

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    Maybe this will help.
    http://how-i-did-it.org/762vs308/chamber.html

    BTW how many manuals do you have and how many have specific 7.62 Nato data? I have several and not one has specific 7.62 Nato data. Lyman 48 is the only one I have that even lists the Nato round and they lump it in with their 308 data . Lyman lists it as follows:
    308 WINCHESTER (7.62x51mm) (7.62 NATO). Other than this, the NATO round appears nowhere in any of my manuals or powder manufacturers data. NATO brass, you bet, reduce powder due to less case capacity, NATO data, Nothing.

    Why? Why NO 7.62x51 NATO load data? There are more than a few rifles chambered in 7.62, so why no data? If the NATO chamber must be loaded down to such anemic pressures, then why no data?

    The answer is simple, there is tons of data it's called 308 Winchester data.

    I know, I know Hornady lists data for the 308 Win. Service Rifle, some will argue that this is 7.62 x 51 NATO specific, not so. If you read the first page of this data you see that it has nothing to do with the NATO chamber as it is not even mentioned. This data is rifle/action specific not chamber specific. Hornady also list the same reduced loads for the 30-06 Service Rifle, which is specific to the Garand.

    Again, take a good look at this Cartridge Spec sheet.
    http://www.ar15.com/media/mediaFiles/348/32231.JPG
    It shows the much talked about NATO max pressure of 50K psi. Take the time to look closely at this load. 172gr bullet powered by 44gr IMR-4895 at 2640fps. It lists the M14 so I will assume a 22 inch barrel.

    Now, gather all of your loading manuals and powder manufactures data and find a similar load.
    Hornady #7 lists 165-168gr bullet(lighter and commercial brass) at 43.3gr IMR-4895 in the 308 Win. Less than the NATO spec sheet.

    Speer #13 lists 165gr bullet (lighter bullet and commercial brass) at 43.0gr IMR-4895.

    Lyman 48 Lists 168gr bullet (lighter bullet and commercial brass) at 42.5gr IMR-4895. They even list pressures at 51,200 CUP. Imagine that 50K CUP NOT 50K psi.

    Sierra #5 lists 168gr bullet (lighter bullet commercial brass) at 41.3gr IMR-4895.

    Nosler #6 lists 165-168gr bullet(lighter bullet commercial brass) at 43gr IMR-4895.

    Hodgdon lists 168gr bullet at 45.4gr IMR-4895 with an MAP of 58K psi, not CUP.

    What does it all mean. It means that according to the Military's own documents their 7.62 NATO round is hotter than all 308 Win data.
     
    Last edited: Sep 4, 2012
  9. steve4102

    steve4102 New Member

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    deleted....
     
    Last edited: Sep 4, 2012
  10. locutus

    locutus Well-Known Member Supporter

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    I use 147 grain W-W or Rem. FMJ, (M-80 ball) loaded with Remington 9 1/2 (MilSpec) primers and a carefully worked up charge of H335 or BLC-2.

    When you reach the velocity of military issue ammo, stop there and call it good. You can exceed military velocities easily, but why would you want to? If you're zeroed with military ammo, handload to the same specs, and you're still zeroed.
     
  11. 25-5

    25-5 New Member

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    Locutus
    I know you know your stuff, but try a heavier bullet. Say 168gr Hornady A-Max and 42 gr Varget or equal. CCI BR primers. Very accurate in my M1A and no problems. Going to try the 178 gr, but that is about as heavy I will go.