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Current Rifle Cartridges
.338 Remington Ultra Magnum, aka .338 RUM
The .338 Remington Ultra Magnum
(.338" Caliber) was introduced in 1999
as one of the (now) 4 Remington Ultra
Magnum, joining the .300" and later the
.375"  7mm Remington Ultra Magnum.
All the Ultra Magnums are based  on the
.404" Jeffery case blown out and necked
down to except their different projectile
diameters.
The .338 Remington Ultra Magnum
delivers 25 % more energy then the .338
Winchester Magnum.
Velocities to over 3,000 Feet per Second  
and energy over 4,300 Foot pounds per
square inch, also projectiles from 160 to
275 grains in weight, this is an excellent
long range hunting cartridge.
Above Picture on the right for size comparison:
Left to Right
:   
7mm, .300, .338 and .375 Remington Ultra Magnums
Far Right:
.404 Jeffery, parent cartridge of the other 4 cartridges.
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