Friday, January 29, 2010

Choosing Hunting Rifle Ammunition: Dangerous Game

Click here to read more.

When choosing ammunition for a particular game animal, the terminal performance of the round you choose is extremely important. Winchester has developed (and trademarked) their CXP (Controlled eXpansion Performance) scale which is used to rate ammunition performance on various types of game. Dangerous game animals, classified as CXP4, are generally thick skinned African game animals such as hippopotamus, rhinoceros, elephant, and Cape buffalo, and can weigh anywhere from 1,000 pounds up to 13,000 pounds or more for large male elephants. As such, when hunting these species, you will need to choose your caliber wisely.

.375 H&H Magnum
Click to view larger image.
The .375 H&H Magnum is generally considered to be a bare minimum for hunting dangerous CXP4 class game. In fact in Africa, the .375 H&H Magnum is the smallest caliber legally allowed for hunting. Loaded with a 300 grain projectile, the cartridge develops a muzzle velocity exceeding 2,600 FPS which results in a muzzle energy of approximately 4,600 ft-lbs (around 6,500 joules). The .375 is very popular with hunters due to its flat shooting characteristics; given a 200 yard zero, bullet drop is only 8.5 inches at 300 yards with a trajectory peak of 2 inches at 100 yards, which makes it very easy to calculate your hold over.

Probably the most famous and widely used cartridge is the traditional .470 Nitro Express. This round, developed by the British for their double rifles, replaced the Eley brothers .450 Nitro Express cartridge which had become banned in a number of countries. The newer bottle necked .470 round pushes a 500 grain "freight train" of a bullet to velocities exceeding 2100 FPS at the muzzle, generating more than 5,000 ft-lbs (nearly 7,000 joules) of force.

There are a number of intermediate sized cartridges such as the .416 Remington Magnum, and the .458 Lott. The .458 Lott is a recently developed cartridge intended to replace the relatively underpowered .458 Winchester Magnum by Jack Lott, a popular gun writer at the time. Lott had the unpleasant experience of having a .458 Winchester Magnum fail to stop a charging Cape buffalo. This life threatening encounter prompted him to design a replacement round based off of a .375 H&H Magnum case. The new .458 Lott brass was slightly longer than the Winchester Magnum, enabling it to be loaded with more powder and giving the bullet an extra 300 FPS. It wasn't until 2002 however when Hornady began manufacturing the ammunition on a large scale commercial basis that the cartridge gained in popularity. Ruger chambered a new rifle for the Lott, the M77RSM Mark II, which soon became very popular with hunters in Africa. The .458 Lott manages to launch a 500 grain projectile out of a 24" barrel with a muzzle velocity of 2300 FPS, giving it a muzzle energy exceeding 5,100 ft-lbs (almost 7,000 joules) making its overall performance as good or greater than the popular .470 Nitro Express.

One of the largest cartridges in common use today is the .505 Gibbs. This monster cartridge is capable of taking down even the largest African game; only the .500 Jeffrey round is more powerful than the Gibbs. Loaded with a 600 grain Australian Woodleigh bullet the Gibbs generates 2,100 FPS muzzle velocity and 5,877 ft-lbs of energy. The Gibbs was made famous by Ernest Hemingway, who wrote and talked about it often. It was favored by one of Hemingway's characters, Robert Wilson, in the story "The Short Happy Life of Francis Macomber".

Bullet selection for these dangerous game cartridges depends on the type of game being hunted. By and large, solid bullets are preferred due to their excellent penetration. They are absolutely necessary for head shots on the largest game such as elephants and cape buffalo. Soft pointed and lead core bullets are only suitable for lung shots, as they rapidly deform from the heavy thick skin of large African game and will not penetrate fully. Expanding bullets for large African game must be well constructed to be able to retain weight and remain intact upon impact. Examples of suitable soft bullets include Trophy Bonded Bear Claw, A-Square, and Barnes Triple Shock X Bullet.

It's critically important to select a caliber that you are capable of shooting but that is also capable of stopping dangerous game animals. Utilizing a caliber that is too large can result in flinching or anticipating recoil and pulling the shot, too small and your quarry may not drop. When hunting dangerous game, your life may very well depend on the ammunition you select.

No comments:

Post a Comment