Another cartridge in the “too good to die” class.
Some cartridges never seem to get a break. Remington introduced the .280 in 1957, but handicapped it by limiting the maximum average pressure to 50,000 CUP, rather than the 52,000 to 54,000 CUP of other modern cartridges. Supposedly this limitation was due to the .280 being specifically designed for Remington’s Model 740 semi-auto and 760 pump-action rifles, though it also simultaneously appeared in their bolt-action Model 725 rifle. Theoretically semi-autos and pumps function more reliably at slightly lower pressures, since their extraction isn’t as powerful as a bolt action’s.
So why was the 740 also chambered for the .308 Winchester, with its 52,000 CUP limit? And the 760 had been available for several years in .270 Winchester at 54,000 CUP.
Even when limited to relatively wimpy pressures, the .280 had several theoretical advantages over its competition. It was basically the old 7mm-06 wildcat, with the shoulder of the case moved forward slightly to prevent chambering a .280 round in a .270 rifle. However, 7mm bullets originated with the 7×57 Mauser in 1892, the very early days of smokeless powder. Back then most new military rifles had relatively fast rifling twists to stabilize the heavy roundnose bullets then in vogue. The 7×57’s original ammunition featured a 173-grain roundnose in a rifling twist of 1:220mm, about 1:8-2/3″. Ever since, most 7mm barrels (including those of the .280) have featured a rifling twist of around 1:9″, sufficient to stabilize even very long 175- or 180-grain boattail spitzers. The three original factory loads used 125-, 150- and 165-grain bullets, and handloaders could easily approximate 130-grain .270 or 180-grain .30-06 loads, making the .280 quite versatile.
Unfortunately, the 1950s were also the beginning of a long period of magnum mania. Roy Weatherby started the trend, and eventually the larger companies had to offer their own magnums. In 1959 Winchester introduced three belted magnums, the .264, .338 and .458, all short enough to fit inside the magazines of the cheap 98 Mauser and 1903 Springfield “war surplus” rifles then flooding the market. Remington had to come up with an answer, and in 1962 introduced the 7mm Remington Magnum in a more sedately Weatherby-styled upgrade of their 725/722/721 bolt actions called the Model 700.
By John Barsness
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