The .338 Winchester Magnum
By Chuck Hawks
The .338 Winchester Magnum is the most popular medium bore cartridge in North America, and the only one for which a truly wide range of rifles is available. Winchester introduced the .338 in a Model 70 rifle named the "Alaskan," and it has become the most popular caliber used by professional guides in that vast state.
Factory loads for the .338 Winchester Magnum offer bullet weights of 200, 210, 225, 230, and 250 grains. Reloaders have all of these, plus bullets of 175, 275, and 300 grains in addition. Solids for thick-skinned dangerous game are available, usually in 250 grain round nose style.
Winchester loads their 200 grain Ballistic Silvertip spitzer bullet (BC .415, SD .250) to a MV of 2,950 fps and a ME of 3,864 ft. lbs. At 200 yards the velocity is 2,509 fps and the energy is 2,794 ft. lbs. The MPBR (+/- 3") for this load is about 289 yards.
Remington loads drive a 225 grain Core-Lokt spitzer bullet (BC .435, SD .281) at a MV of 2,780 fps and a ME of 3,860 ft. lbs. At 200 yards the velocity is 2,374 fps and the energy is 2,815 ft. lbs. The MPBR of this load is around 270 yards.
Federal's Premium Safari Rifle load pushes a 250 grain Nosler Partition spitzer bullet (BC .473, SD .313) at a MV of 2,660 fps and a ME of 3,925 ft. lbs. At 200 yards the velocity is 2,300 fps and the energy is 2,925 ft. lbs. This load has a MPBR of approximately 265 yards.
While there is a wide range bullet weights available for .338 rifles, the 200-250 grain bullets remain the most popular with reloaders. I use the 225 grain Hornady Interlock SP as the all-around bullet in my .338 Win. Mag. rifle.
A number of powders perform well in the .338 Win. Among those often recommended are H414, H4350, IMR 4350, IMR 4831, and RL-19.
Here are some specifications of interest to .338 Win. Mag. reloaders: bullet diameter .338", primer size Large Rifle Magnum, maximum COL 3.34", maximum case length 2.50", MAP 54,000 cup.
The sixth edition of the Hornady Handbook of Cartridge Reloading shows that 58.7 grains of H4350 powder can drive a 200 grain bullet to 2500 fps, and 73.9 grains of H4350 can drive the same bullet to a MV of 3000 fps.
A 225 grain Hornady bullet can be driven to a MV of 2300 fps by 58.2 grains of IMR 4831, and to a MV of 2800 fps by a maximum load of 69.8 grains of IMR 4831. Hornady's figures were taken from the 24" barrel of a Winchester Model 70 rifle, and all loads used Hornady brass and Winchester WLRM primers.
Data from the Barnes Reloading Manual Number One shows that a 250 grain Barnes bullet in front of 65.0 grains of H4350 can be driven to a MV of 2574 fps, and to a MV of 2730 fps by a maximum load of 70.0 grains of the same powder. Velocities from the Barnes Manual were chronographed in a 24" barrel.
The Barnes Reloading Manual also shows that if their 225 grain X-Bullet (BC .482) at a MV of 2,800 fps is zeroed to strike 3.05 inches high at 100 yards, it will be about 4 inches high at 200 yards, and 4.05 inches low at 300 yards. These figures apply to a rifle with a scope sight mounted 1.5 inches over the bore. Incidentally, that bullet still has 2,083 ft. lbs. of energy at 300 yards!
Note: The complete article about the .338 Winchester Magnumcan be found in its entirety on the Rifle Cartridge Page.
Copyright 2004, 2013 by Chuck Hawks. All rights reserved.