Comments

1. On February 7, 2021 at 11:52 pm, BRVTVS said:

   Due to improved powders, the 308 of today matches the ballistics of the original military loading of the 30-06.

2. On February 8, 2021 at 11:49 am, John said:

   Another ballistic battle in the “Forever War” of these calibers.
   As BRVTVS states; as far as military equivelence goes it is a moot discussion.
   As far as hunting goes; the “06” has the edge in loading heavier bullets and powder charges
   at the slight cost of using a longer action.
   However; both, when loaded at the same proper bullet weight for the job will stop any animal in North America.
   Still, discussing it is a decent way to spend some time in a comfy recliner on a very cold day.

3. On February 8, 2021 at 1:54 pm, billrla said:

   Why is it that everything I own and everything I do is now old fashioned?

4. On February 9, 2021 at 1:07 pm, TwoDogs said:

   It’s not quite dead yet.

5. On February 10, 2021 at 6:05 pm, Georgiaboy61 said:

   @ BRVTVS

   Re: “Due to improved powders, the 308 of today matches the ballistics of the original military loading of the 30-06.”

   The venerable long-action 30-06 cartridge saw the U.S. military through WWI, WWII and Korea, along with countless small wars and actions over its service life, but it was recognized at some point that modernizing it might make sense. Short-action cartridges offer certain reliability and other benefits to crew-served automatic weapons, and a shorter, lighter cartridge would allow logistics benefits as well.

   There was a good deal of political gamesmanship about just what form the new cartridge ought to take, vis-a-vis the brand new North Atlantic Treaty Organization (NATO) alliance. However, given that the U.S. was the de facto leader and had the most economic and military clout – in the end the choice of the U.S. Army Ordnance Department won out, and the 7.62×51 cartridge was adopted.

   In metric, the old ’06 was 7.62x63mm, so all the new cartridge really did was shorten the existing U.S. service cartridge 12mm, or roughly half-an-inch. This was possible, as noted above, by advances in propellant technology made since the introduction of the 30-06 150-grain M2 Ball/FMJ round in the late 1930s.

   The new 7.62 NATO or .308 Winchester as it became known commercially, duplicated the performance of the old M2 round in the new 7.62×51 M80 Ball/FMJ service cartridge, which attained ~ 2805 fps at the muzzle when fired from a 22-inch barrel.

   The long-action 30-06 case provides room for significantly more propellant than its shorter offspring, a fact which – bullets identical – allows it to be loaded to higher muzzle velocities and longer range in comparison to its short-action successor. However, since the difference in case length and volume really only becomes an issue at or above 180-grains, this isn’t a factor since the U.S. military had no standard issue small-arms ammunition of more than 180 grains in bullet weight, for either cartridge.

   Since the M-1 Garand was designed around bullets in the 147-178-grain range, using powders in the burn rate class of IMR-4895 and IMR-4064, no bullets heavier than 180-grains were routinely used in these rifles, or in the Browning BAR and Browning M1919 medium machine gun. Since the M-14 had a self-compensating gas system, and was somewhat more-forgiving of different loads than the less-advanced M-1 gas system, greater experimentation could have been done with it, but ordnance stuck with the same range of weights/styles of projectile.

   Make no mistake, however, the 30-06 – when loaded to its true potential – is undeniably superior in performance to its shorter sibling. The .308 Winchester/7.62 NATO is pushing its maximum pressure/MV limits when loaded with a 147-grain slug @ 2805 fps. However, the same bullet can be pushed considerably faster (~ 2900-2950 fps) in the 30-06, by using a slower powder and a bolt-action firearm, for example, as would many hunters. And the 30-06 can easily handle projectiles in the 200-220 grain class, which are really more than the short-action .308/7.62 NATO prefers for optimum performance.

   As a long-range cartridge, even when loaded with heavy, relatively-efficient bullets, most of the time the .308 runs out of gas in the 1000-1200 yard range envelope, depending on specific local conditions. Pushed to its maximum, however, and using state-of-the-art propellants and highly-efficient 200 grain or more bullets, the 30-06 achieves near-magnum performance and is a legitimate 1400-1500 yard cartridge in terms of supersonic range.

   In brief, then, the .308 can do almost everything its big brother can do, but not quite everything….

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