6.5x55 barrel will last 10,000 rounds. That was the idea when the Swede's adopted it in 1894. I'm not seeing a 6.5-.284, .260, or any other 6.5 coming close. The 6.5x47 has a less then 70fps advantage using 139-140gr bullets. The 6.5x55 can still shoot 152, 155, 160 gr more effectively. If you have a '98 action or other newer action, the 6.5x55 can be ramped up a bit if max velosity is your game. If you want a hunter, the 6.5x55 offers heavy bullet options the others don't. Elk at 300 yards is on the table w/ a well made bullet. It really comes down to what you want to hunt. The 6.5x47 was made for 300 meter target shooting, the rifles reflect that. It did win the 600 meter w/ Norma ammo.
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