Thread: .338 Lapua?
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Old February 8, 2013, 07:21 AM   #27
Bart B.
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Join Date: February 15, 2009
Posts: 4,642
Allaroundhunter, the shooters physics has to be included because it determines how much the rifle's barrel moves while the bullet's going down the barrel. Nobody holds a shoulder fired rifle exactly the same way for every shot. More recoil means more irregular shooter and rifle movement during barrel time. Therefore, nobody shoots a rifle off their shoulder as accurate as the rifle will shoot from a machine rest. While a rifle and its ammo may well shoot several consecutive 1 inch 10-shot test groups at 600 yards clamped in a free recoiling machine rest (yes, that's been done), the best shooter on this planet could only shoot groups off the shoulder at 600 yards of about 6 inches. This is why the 26 and 28 caliber shoulder fired long range match rifles have outscored what the heavier recoiling 30 caliber ones did. But the big 30 calibers are still holding their own in free recoil heavy rifle benchrest disciplines.

Sierra's 30 caliber 220-gr. HPMK bullet's BC is only .629; there's a higher one made by Sierra; the 240-gr. HPMK at .711. I think you made a typo.

Better ballistics does not equal better accuracy. Better ballistics means less velocity drop and wind drift over a given range. Better accuracy is more repeatable ballistics regardless of their numbers. It's been proved over the decades of shooting that better accuracy is preferred to better ballistics.

But there's more to it than just recoil. No wonder the 33 caliber cartridges have not fared well competiting with smaller calibers at long range: http://www.6mmbr.com/gunweek057.html Folks having a free choice of calibers, 33's are not among the best for accuracy. Ballistics ain't important in accuracy games.

That reference to the .300 Win Mag outperforming the .338 Lapua in Army tests was emailed to me from a former US Navy SEAL Team commander and isn't on the internet as far as I know. As I remember, the .300's were using 190's and 200's for the tests. Everything that happens is not on the internet for public view.
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