One of the most hotly debated topics among North American hunters is what hunting ammunition is appropriate for medium game. Medium game, also referred to as the "CXP2 Class" or "Controlled Expansion Class 2" by Winchester, includes white tailed deer, mule deer, pronghorn antelope, wild sheep, and caribou. These are by far the most popular game animals in North America, making the ammunition used to hunt them some of the best selling rounds.

Some medium game, such as smaller Texas white tailed deer, can be humanely harvested using smaller ammunition while larger and heavier game such as mule deer should only be harvested with more powerful ammunition capable of penetrating more deeply. This broad performance range places unique demands on ammunition used to bring down animals in this class. Some hunters use more powerful .308 and .30-06 caliber ammunition when hunting medium game, but there is actually a unique group of ammunition slightly less powerful than these .30 caliber standards that is perfectly suited for the CXP2 class.

.30-30 Winchester
The first cartridge in our list was actually the first .30 caliber round designed to be propelled by smokeless powder. The .30-30 cartridge has probably brought down more deer than any other rifle cartridge. Put into production in 1895 for the Winchester lever action rifle, the .30-30 soon gained popularity as the smokeless powder it used allowed for faster follow-up shots and significantly reduced fouling in the barrel and action. This soft shooting round has an effective range of only 200 meters but with a 170 grain flat point bullet it hits hard enough to drop all but the largest CXP2 Class animal.

.243 Winchester
The .243 Winchester is a popular round for youths and new shooters who dislike the harsh recoil of larger calibers. Though it is soft shooting,the .243 is more than capable of taking down any medium sized game animal, from feral hogs to large white tailed deer. BVAC's 100 grain Grand Slam is an easy to shoot round with a maximum point blank range out past 300 yards, depending on the size of the game animal. Hornady's Varmint Express topped off with a 58 grain V-Max on the other hand is an extremely fast and flat shooting cartridge that travels over 3750 feet per second at the muzzle, making it an excellent varmint round out to 200 yards. Their Superformance ammunition is even hotter, throwing a 58 grain projectile down range at over 3925 feet per second.

.270 Winchester
The .270 Winchester cartridge was released in 1925 for the Model 54 bolt action rifle. It was praised highly by writer Jack O'Connor who wrote at length about it in Outdoor Life and other publications, but the round never enjoyed great success for nearly 20 years. Then, after World War II, it saw an enormous surge in popularity becoming one of the most widely chambered calibers for hunting rifles across the globe. Loaded with a 100 Grain cartridge, Remington Core Lokt PSP achieves a muzzle velocity in excess of 3,300 feet per second. This extreme velocity makes the .270 a very flat shooting round with devastating terminal ballistics. Loaded up in a heavier 150 Grain Federal with Sierra Game King the round is effective on larger game animals like moose or elk. The middle weight  130 Grain BVAC Grand Slam is a good all-around cartridge for hunting a variety of medium sized game.

.25-06 Remington
For decades the .25-06 was just a wildcat round created from a necked down .30-06. When Remington began producing the round as a factory load in 1969 however, it experienced a surge in popularity. Topped off with a 120 Grain Speer Grand Slam bullet the BVAC .25-06 cartridge generates a muzzle velocity of 2898 feet per second, and when topped with an 85 Grain Nosler Ballistic Tip Federal's V-Shok load reaches a velocity of over 3550 feet per second. This zippy little round may be a small caliber, but its flat trajectory and devastating terminal ballistics help it to remain popular among varmint and medium game hunters. Despite the small size of the .25-06 it has superior sectional density at higher bullet weights. The 115 Grain Winchester Ballistic Silvertip has a ballistic coefficient of 0.446, giving it penetration and performance comparable to larger .30 caliber rounds.

7mm-08 Remington
The 7mm-08 Remington cartridge is versatile, able to work equally well on medium sized game in dense forests as it is at long ranges on plains animals. Like the other sub-.30 caliber rounds listed above, the 7mm-08 makes up for it's smaller diameter with greater sectional density. Topped off with a 145 grain Speer Grand Slam, BVAC's 7mm-08 load has a ballistic coefficient that exceeds 0.32, and with a heavier 162 grain Hornady A-Max the ballistic coefficient tops out at 0.625. This incredible sectional density gives the 7mm-08 excellent penetration and outstanding long range stability. Despite the heavier bullet and greater energy of the 7mm-08, the recoil is only slightly more than the .243. The long range performance of the 7mm-08, with an effective range over 600 yards, also makes it popular with target shooters.

Larger Calibers and The Importance of Sectional Density
Except for the .30-30, every cartridge discussed here is smaller than the most .30 caliber hunting rounds. Still, they maintain adequate performance, especially with heavier bullets, due to their sectional density.

What is sectional density? The sectional density is the ratio of the diameter of the round and its weight. Computing the sectional density of a bullet is fairly straight forward: simply take the mass of the bullet and divide it by the diameter (caliber) squared. A heavier bullet will have a better (higher) sectional density than a lighter bullet of the same caliber. For this reason, bullets that are lighter tend to have a lower ballistic coefficient than heavier bullets (assuming of course that the bullets have the same aerodynamic shape). Heavier bullets will decelerate less due to the higher inertia their increased weight gives them.

For hunting rounds, this means that bullets with higher sectional densities will penetrate better than bullets with lower sectional densities. Heavy .270 loads and most 7mm-08 loads are capable of performing nearly as well as larger .308 loads of the same weight because of this. Still, though they have similar performance, both the .270 and the 7mm-08 generate around 17% less recoil than a .308 round of the same weight. Because of their more streamlined shape, these cartridges also have flatter trajectories than their .30 caliber cousins.

The popular .308 and .30-06 hunting cartridges are commonly used for hunting medium sized game, but cartridges of this size are what we might consider super-adequate. These .30 caliber cartridges are rounds that work equally well on medium as well as heavy game. With the proper shot placement on medium game you can harvest your quarry without damaging the meat, while a solid hit on a larger animal such as an Elk or Moose will also work just as well.

Can you take a white tailed or mule deer with a .308 or .30-06? Sure you can. But do you need that much gun? Probably not. When looking for your next hunting rifle, look to some of the smaller calibers. They are more than enough to take almost any hooved game animal in North America.