Re: Caliber Choices - Comparison and Applications
The 375 Allen Magnum loaded with the 350 gr. SMK offers nearly identical trajectory as its 338 caliber sibling out to 1200 yards yet has a significantly larger kenetic energy payload. While it gives up a bit in flexibility with fewer bullet options, it also offers mearsurably longer throat life and more punch on heavy game at extreme range.
Parent Case: 408 Cheyenne Tactical
Recommended Bullets: 350 grain Sierra Match King
Recommended Powders: Hodgdon Retumbo
Recommended Primers: Federal 215 Large Rifle Magnum
Velocity Performance:
Bullet Weight Velocity (33" barrel length)
350 gr. 3300 fps
Ballistic Performance:
Bullet Weight: 350 gr. Sierra Matchking @ 3300 fps, 500 yard zero, 10 mph
Yardage velocity wind drift Energy TOF(sec)
600 2660 fps 11.0" 5499 ft/lb 0.607
1000 2281 32.7" 4043 1.095
1400 1936 69.2" 2912 1.665
1800 1625 124" 2051 2.343
2200 1358 202" 1432 3.152
2600 1154 308" 1034 4.116
2800 1082 371" 910 4.656
Recommended Uses: Big Game Hunting is the major purpose for the 375 Allen Magnum but with the larger bore diameter it also has found some use in extreme range target shooting. Like its smaller caliber brother 338 A.M., the 375 Allen Magnum is extremely effective for big game hunting at long to extreme range. With the larger frontal area and heavier bullet weight, the 375 A.M. is suitable for the heaviest big game animals and its especially suited for hunting elk, moose and similiar size big game at ranges past 1000 yards. It also is well suited for smaller big game species at any supersonic velocity range but it is better suited toward heavier game species.
Effective Range: With its primary bullet, the 350 gr. Sierra Matchking, the 375 Allen Magnum will sustain supersonic velocity to a range of roughly 2800 yards give or take slightly depending on elevation. With the weight and diameter of this bullet, the 375 Allen Magnum will easily harvest medium big game at any supersonic range assuming the hunter has the ability to put the bullet through the vital area of the target animal. Even if bullet expansion is minimal, the 375 caliber projectile is very effective at cleanly harvesting big game because of its large frontal area and large amount of tissue displacement., For heavier game, its recommended to keep shots to to less then 1 mile (1760 yards) simply because of bullet time of flight and not nessesarily because of lack of terminal performance at longer distances.
Pros: Fully formed, correct headstamped custom brass available from APS with rifle orders. Extreme terminal and ballistic performance. BR class accuracy. Longer barrel life then 338 A.M.(estimate 20-25% longer). Comfortable recoil levels with the Xtreme Heavy Sporter rifle platform. Very similiar trajectory to 338 A.M. but with more terminal authority on heavier big game.
Cons: Requires custom receivers because of the size and overall length of the 375 A.M. ammunition. Rifles are long and relatively heavy starting at around 16 lbs ready to hunt with. Recoil is noticably heavier then the 338 A.M. but not punishing in any way. Choice of quality long range bullets is relatively limited compared to 338 caliber.