Despite the excessive report and recoil produced by magnum power rifle cartridges, big game hunters have long displayed a passion for larger and more powerful rounds for perusing large and/or dangerous game species.
In fact, two of the first modern rifle cartridges to provide “magnum” level performance were the .30 Newton which was introduced in 1913 followed by the .300 H & H Magnum in 1925. Then, in 1943, Roy Weatherby began to introduce a series of magnum level belted rifle cartridges based on standard length cases so that they could be cycled in standard length actions.
This, in turn, caused Winchester to develop and introduce three new rifle cartridges called the .264 Winchester, the .338 Winchester and, the .458 Winchester in 1958. However, this left an obvious gap between the .264 caliber (6mm) round and the .338 caliber round and thus, Winchester eventually introduced the .300 Winchester Magnum in 1963 specifically to fill this gap and, it has been a hunter’s favorite ever since.
However, there is a relatively new rifle cartridge on the market today called the 6.5mm Creedmoor who’s performance can equal that of the .300 Winchester magnum. In fact, although the 6.5mm Creedmoor was originally developed as a target rifle cartridge, its superior ballistics and terminal performance are fast bringing it to the attention of medium sized game hunters because, with some loads, this cartridge is capable of duplicating the muzzle velocity and/or trajectory of the .300 Winchester Magnum (if not its terminal performance). But, this is especially important because its overall length allows it to cycle in short action bolt action rifles and AR-10 semi-automatic actions while producing less recoil than a .308 Winchester Magnum cartridge. Thus, when looking at a comparison of the 6.5mm Creedmoor vs. the .300 Winchester Magnum cartridges, it quickly becomes apparent that they both have a lot to offer.
So, what is it about the .300 Winchester Magnum that has made it such a popular big game hunting cartridge for so many years? Well, as mentioned previously, the .300 Winchester Magnum was specifically designed to fill the gap between the .264 Winchester Magnum and the .338 Winchester Magnum cartridges and thus, due to its .30 caliber bullet and its magnum level muzzle velocity, it was destined to be an immediate success among both medium and big game hunters and, even some target shooters. So, to design the cartridge, Winchester started with the .338 Winchester Magnum as the parent case and then they moved the shoulder forward by 0.156 inches and extended the overall length of the case by 0.120 inches which, interestingly, caused the cartridge to have a neck shorter than the diameter of the bullet while also increasing the case capacity.
Nonetheless, many hunters feel that the .300 Winchester Magnum is the best medium caliber, large game, hunting cartridge readily available because bullet weights can range from as little as 130 grains to as much as 220 grains and, it can fire a 200 grain bullet at an average speed of 2,930 fps and a 210 grain bullet at an average speed of 2,665 fps which delivers 3,813 ft./lbs. and 3,313 ft./lbs. of kinetic energy respectively. Therefore, the 130 grain loads are a good choice for varmints and medium sized game at closer ranges while 150 grain loads are well known for fast incapacitation of medium sized game and the 200 grain loads can be humanely used on large game species such as Elk and Moose while, the 220 gain loads are sufficient for large and dangerous game such as Brown Bears provided that the right bullet design is chosen and the hunter’s shots are well placed. So, all things considered, it is really quite easy to understand why the .300 Winchester Magnum cartridge is so popular among long range shooters and big game hunters.
However, even though the 6.5mm Creedmoor is not quite as versatile as the .300 Winchester magnum, it is nonetheless fast becoming a very popular cartridge among medium sized game hunters despite the fact that it was originally designed as a match cartridge. Even so, the 6.5mm Creedmoor still has a much more colorful origin than the .300 Winchester Magnum in that its parent case is the .30 Thompson Center (aka .30 TC) which Thompson introduced in 2007 in conjunction with their new line of bolt action rifles as their attempt to design a .30 caliber cartridge with an overall length equal to that of the .308 Winchester Magnum but, with the ballistic performance of the .30-06 Springfield cartridge. Thus, the 6.5mm Creedmoor was created by reducing the neck size of the .30 TC case from .030 inches to .264 inches which also creates a slightly steeper shoulder angle while also slightly reducing case capacity.
But, even so, bullet weights can range from as little as 120 grains to as much as 147 grains and, AAMI test data shows that the 6.5 mm Creedmoor can fire a 129 grain bullet at 2,940 fps and a 140 grain bullet at 2,690 fps which delivers 2,477 ft./lbs. and 2,250 ft./lbs. of kinetic energy respectively. Thus, although this cartridge was specifically designed for match shooting because many formal target shooters feel that the 6.5mm bullet diameter provides the optimum Ballistic Coefficient and Sectional Density which results in superior downrange accuracy, many experienced hunters feel that the .264 caliber bullet provides superior energy transfer and optimum penetration on medium sized game animals even at relatively long ranges. Thus, it is an excellent choice for game species such as White Tail Deer, Mule Deer, Antelope, Mountain Goats and, Dall Sheep as well as for hunting varmints such as coyotes.
So, as you can see when comparing the 6.5 Creedmoor vs. the .300 Winchester Magnum, although the .300 Winchester Magnum cartridge has been available to hunters for far longer than the much newer 6.5mm Creedmoor cartridge has, due to the fact that some loadings of the 6.5mm Creedmoor are capable of equaling both the muzzle velocity and the trajectory of the more powerful .300 Winchester Magnum while also producing less felt recoil due to firing lighter bullets, the 6.5mm Creedmoor is starting to encroach on the seemingly everlasting popularity of the .300 Winchester Magnum. So, if you are looking for a rifle for hunting medium sized game species, then you might want to consider what just might turn out to be the Golden Rifle Cartridge for hunting medium sized game species although, in the contest of David represented by the 6.5 Creedmoor vs. the .300 Winchester Magnum representing the giant Goliath, then the .300 Winchester Magnum is very likely to retain its crown as king of the medium bore, large game, cartridges.
Written by Bill Bernhardt
Bill Bernhardt is a professional outdoor/wildlife writer and is a professional fly fishing instructor and guide as well as a professional hunting guide. He is an avid outdoorsman with expertise in fly fishing, hunting, firearms, archery, cutlery, outdoor survival, camping, and kayak touring.