Compared: The .350 Remington Magnum and 9.3x62mm
By Chuck Hawks
The 9.3x62mm was designed by the famous German gunsmith Otto Bock around 1905. Hornady announced in 2010 that they would offer factory loaded ammunition in 9.3x62mm caliber. This means that they will join Stars & Stripes (USA), A-Square (USA), Nosler (USA), Norma (Sweden), Sako (Finland) and Sellier & Bellot (CZ), among others, in recognizing this useful medium bore caliber (9.3mm = .366") that is widely used for hunting heavy game in both Europe and Africa, but less so in North America. Of course, now that a major American ammo company is supporting the cartridge, that may change. In the US, 9.3x62mm rifles are available from CZ, Sako, Tikka, Merkel and possibly others. Factory loaded bullet weights are 232, 250 and 286 grains.
The .350 Remington Magnum was introduced in the early 1960's as an improved, short action equivalent to the .35 Whelen, which was still a wildcat at that time. It is based on a shortened 7mm Rem. Mag. case and was the first true short magnum cartridge. The .350 Mag. case has slightly more capacity than the .35 Whelen case or the 9.3x62 case and a belt for positive headspacing. The latter is a selling point, as the small 17.5 degree shoulder of the latter two cartridges doesn't leave much area with which to maintain proper headspace.
The .350 Rem. Mag. seems to drift in and out of favor. The Ruger M77R and Remington Model Seven are the latest rifles chambered for the cartridge. Remington, alone of the big U.S. ammo manufacturers, loads for the caliber, but specialty manufacturers, such as Stars & Stripes, are reliable sources of .350 Rem. Mag. factory loaded ammunition. Remington factory loads are supplied with 200 grain Core-Lokt bullets at a muzzle velocity (MV) of 2775 fps and Stars & Stripes offers 200 grain (MV 2892) and 225 grain (MV 2713 fps) Barnes TSX bullets in their Production ammo line and pretty much whatever you want in custom loads. I, for example, have standardized on Stars & Stripes Custom Ammo using a 225 grain Nosler Partition bullet at a MV of 2550 fps for my .350 Mag. Ruger M77R, while Guns and Shooting Online Technical Assistant Jack Seeling has standardized on Stars & Stripes Custom Ammo using a 250 grain Nosler Partition bullet at a MV of 2500 fps for his .350 Remington Model 673 rifle.
The lighter bullet weights in each caliber are designed for shooting smaller game animals, but for hunting the heavy game that is the reason for the existence of both cartridges, it is the heavy bullets that shine. That would be the 250 grain bullet in .350 Rem. Mag. and the 286 grain bullet in 9.3x62mm. We will compare these bullet weights in this article.
The new Hornady load for 9.3x62 uses a 286 grain Interlock SP-RP bullet at the standard European MV of 2360 fps. The aforementioned Stars & Stripes Custom Ammo load using a 250 grain Nosler Partition bullet at a MV of 2500 fps will represent the .350 Rem. Mag. Both of these loads can be duplicated by reloaders. We will compare these loads in terms of kinetic energy, trajectory, bullet cross-sectional area, sectional density, killing power and recoil.
Kinetic energy is a measure of the ability to do work. Energy powers a bullet's expansion and penetration in a game animal. Bullet penetration and expansion are very important factors in killing power and energy is a useful comparison, as long as similar cartridges are compared. Following are the energy figures in foot-pounds at the muzzle (ME), 100 yards, 200 yards and 300 yards.
There is little to choose between our two cartridges in terms of kinetic energy out to 100 yards. At longer range, the sleek .35 caliber Nosler Partition bullet at higher velocity achieves a minor energy advantage over the 286 grain 9.3mm bullet. However, it is unlikely that any game animal could live on the difference.
Trajectory is important because the flatter a bullet shoots the less the shooter needs to compensate for bullet drop as ranges increase. The following trajectories, shown in inches above or below the line of sight at the muzzle, 100, 200 and 300 yards, are computed for a 200 yard zero (which is close to the zero distance for the MPBR of both cartridges) and assume an optical sight mounted 1.5" over bore.
As can be seen from these figures, the .350 Mag. shoots somewhat flatter than the 9.3x62 across the board, attributable to its higher velocity.
Bullet cross-sectional area
The fatter a bullet is the bigger the wound cavity it is likely to make and the more tissue it destroys as it penetrates. Bullet cross-sectional area is an important factor in wound ballistics. The actual diameter of .350 Rem. Mag. bullets is .358" and the actual diameter of 9.3x62mm bullets is .366". All bullets of a given diameter (caliber) have the same cross-sectional area regardless of shape or weight. Following are the bullet cross-sectional areas for our calibers in square inches.
That the frontal area of a .366" bullet is greater than a .358" bullet is understood. The slightly larger 9.3mm bullet should make a slightly wider wound cavity, increasing its killing power, other things being equal.
Sectional density (SD) is defined as a bullet's weight (in pounds) divided by the square of its diameter (in inches). It is important because, other factors being equal, the higher its SD the deeper a bullet will penetrate. Shape (round nose or pointed) has no affect on SD, just the bullet's mass and diameter. Penetration is an important factor in the length of the wound channel and the amount of tissue disrupted. Here are the sectional densities for the bullets used in the loads compared in this article.
Based on its superior SD, other things being equal, the 286 grain 9.3x62 bullet should penetrate deeper than the 250 grain .350 bullet. This is important when hunting very large and dangerous game, as it is absolutely critical that the bullet reach the vitals.
There are many ways to estimate the killing power of big game cartridges. Some seem to correlate with observed results in the field and some are simply concocted to promote the author's point of view (extreme velocity, heavy weight bullets, "KO" value, etc.). One of the newer, and better, methods of estimating killing power is the "Hornady Index of Terminal Standards" (HITS), which includes factors such as bullet weight, sectional density, ballistic coefficient and impact velocity. HITS are calculated for a range of 100 yards, a typical distance for shooting large and dangerous game.
A hits rating of 901-1500 is considered adequate for large game, such as elk, eland, kudu and moose. HITS scores over 1500 are considered adequate for hunting dangerous game, so the .350 Rem. Mag. and 9.3x62 are cartridges to consider for your next Alaskan moose and grizzly bear hunt. The 9.3x62 would be preferable for hunting dangerous game, but the .350 Mag. is no slouch. Both are clearly more than adequate for killing large game.
Lower recoil is a big help in achieving proper bullet placement, as everyone can shoot more accurately with a rifle that kicks less. The truth is that all powerful medium bore calibers, including the .350 Rem. Mag. and 9.3x62, generate more recoil than most shooters can tolerate in standard weight hunting rifles. They do not, however, kick as hard as most of the magnums used for hunting heavy game.
If, as commonly generalized, the average shooter and hunter simply cannot withstand repeated recoil energy in excess of 20 ft. lbs., both of these cartridges are apt to promote flinching. These are not good cartridges for recoil sensitive shooters and even experienced shooters should take them in small doses.
To compute recoil you need to know the rifle weight, bullet weight, MV and the weight of the powder charge. Such computations are approximate, but adequate for our comparative purposes. Here are the recoil energy (in foot pounds) and velocity (in feet per second) figures for our comparison loads when fired in 8.5 pound rifles:
As you can see from these numbers, both cartridges are well over the 20 ft. lb. maximum and the 9.3x62 kicks harder than the .350 Mag. That is the price for throwing a bigger bullet with greater SD. When killing power is increased, your shoulder must pay the price. For most purposes the .350 will get the job done with less pain. It has also proven reliable for killing grizzly bears, jaguar and leopard. If lion, buffalo, rhino or elephant are on the menu, the 9.3x62 is the minimum cartridge allowed for use on such creatures in most African countries. It is also the lightest kicking cartridge legal for use on these animals.
Neither the .350 Remington Magnum nor 9.3x62mm are very popular in North America, probably because we don't have a lot of game that requires such powerful cartridges. However, although they are not usually found on the shelves in big box sporting goods stores, both rifles and ammunition are available to the hunter who wants them and these cartridges are more reliable slayers of big beasts than many more popular cartridges, most of which kick just as hard. There is not a marked difference in their capability unless dangerous African game is sought, in which case the 9.3x62mm would be the better (and legal) choice.
These are versatile, as well as powerful, cartridges. If you can stand the recoil, they shoot flat enough to serve as general purpose CXP2/CXP3 class game hunting cartridges and they excel for harvesting large game. This is worth remembering if you hunt innocuous game in an area populated by potentially dangerous game. I have, for example, hunted Catalina goats on at least three occasions in an area also frequented by American bison and wild boar. The first time I carried a .260 Remington rifle, but after several close encounters with bison, on subsequent hunts I carried my Ruger M77R in .350 Rem. Mag. Overkill for goats, to be sure, but comforting under the circumstances.
Copyright 2010, 2012 by Chuck Hawks. All rights reserved.