The .338 Remington Ultra Mag
By Chuck Hawks
In 2001 Remington introduced their .338 Ultra Mag, based on the .300 Ultra Mag case necked up to accept .338" bullets. This huge cartridge requires a long magnum action as well as an extra long barrel (28" is recommended and 26" is the practical minimum). Remington Model 700 rifles chambered for the .338 Ultra Mag are supplied with 26" barrels. Shorter barrels will degrade the big .338's performance and increase the cartridge's already formidable muzzle blast.
Remington offers two factory loads for the .338 Ultra, both with 250 grain bullets. One uses a 250 grain Core-Lokt bullet and the other a Swift A-Frame bullet, both at a claimed muzzle velocity (MV) of 2,860 fps and muzzle energy (ME) of 4,540 ft. lbs. The figures at 200 yards are 2440 fps and 3303 ft. lbs. Remington's trajectory table shows that if a rifle firing the A-Frame bullet is zeroed at 200 yards, the bullet will hit +1.7" at 100 yards, 0 at 200 yards, and -7.6" at 300 yards.
If this load were zeroed to hit 3" high at 100 yards its trajectory would look like this: +3" at 100 yards, +2.5" at 200 yards, +0.1" at 250 yards, -3.7" at 300 yards, and -9.4" at 350 yards. This would seem like a better bet.
According to Hodgdon reloading data, a maximum load of 101.0 grains of RETUMBO powder can drive a 250 grain Hornady spire point bullet to a MV of 2964 fps. Reloaders also have 200 and 225 grain bullets with which to work, although given the size of the .338 Ultra case the 250 grain bullet would seem to be the best choice for most applications.
Recoil, of course, it the biggest drawback to the .338 Ultra Mag. A Remington Model 700BDL rifle in .338 Ultra weighs about 7.5 pounds, or approximately 8.5 pounds with a scope and mount. A rifle of weighing 8.5 pounds is going to pound the shooter with about 43.1 ft. lbs. of recoil energy. This is over twice what the average shooter can tolerate.
It seems unlikely that this new outsized .338 will challenge the established .338 Winchester Magnum's popularity, but it might give the .340 Weatherby Magnum, which offers similar ballistics, a run for its money.
Copyright 2001, 2012 by Chuck Hawks. All rights reserved.