The .308 Winchester has been one of the most wildcatted cartridges in modern times. Itself a derivative of the older .300 Savage, the .308 Winchester has spawned some of the most popular cartridges in America, including the .243 Winchester and the 7mm-08 Remington. But for all the variations on the basic case design, one glaring hole remained until recently.
While the .308 had been necked down for decades, the .358 Winchester was the only derivative cartridge that featured wider bullets in a necked-up .308 case. A popular cartridge in lever-action rifles and with deep woods hunters, the .358 Winchester seemed to take care of the need for a larger-caliber cartridge based on the .308 case. But the introduction of the .338 Federal in 2006 may have disproved that.
Why there wasn’t a cartridge in between the .358 and the .308 is hard to fathom. While there have always been 8mm wildcats of the .308, none of them achieved much popularity due to the fact that Americans just don’t particularly care for 8mm bullets. And with .330-.338 bullets being most popular in larger cartridges such as the .318 Westley Richards, .333 Jeffery, .333 OKH, and .338 Winchester Magnum, there just wasn’t much demand for .338-diameter derivatives of the .308 Winchester. Or so it seemed. The introduction of the .338 Federal highlighted some of the reasons some shooters might like to try a mid-caliber .308 derivative.
With its larger bore diameter, the .338 Federal can drive bullets of equal weight to higher velocities than the .308. 180-grain bullets can be pushed at up to 2,800 feet per second, while 225-grain bullets can be pushed at up to 2,500 feet per second, for muzzle energy of about 3,100 foot-pounds. That compares very favorably to the .30-06 Springfield, and doesn’t leave much on the table when compared even to the .338-06. Those looking for even heavier bullets can load 250-grain bullets, which should be able to be pushed to at least 2,300 feet per second.
The bullet construction of many .338-caliber bullets is intended for use against larger game, up to and including grizzly bears. So hunters using the .338 Federal don’t have to fear that their bullets won’t stand up to heavy and dangerous game. Because of its parentage, the .338 Federal can be chambered in any firearm that normally is chambered in .308 Winchester or 7.62x51mm NATO, including semi-automatic battle rifles such as the FN FAL and AR-10/DPMS-308. And because .338 bullets are narrower than .358 bullets, some magazines for those rifles may be able to feed .338 Federal with minimal to no modifications.
The two knocks on the .338 Federal are cost and availability. Factory ammunition generally starts at $1 a round, versus 33 cents for steel-cased .308 and 50-55 cents for brass-cased .308. For high-volume shooters or those with semi-automatic rifles, that makes handloading the .338 Federal almost a necessity. Availability also isn’t quite as good as .308, although most big box stores and sporting goods stores should carry at least some .338 Federal ammunition.
If you’re looking for something that has a little more punch than 7.62×51 M80 ball in your battle rifle, or something with a little more hunting power in your bolt-action rifle, you might find the .338 Federal to be a good choice. Just make sure to stock up on ammunition and reloading accessories to ensure a steady supply of ammo.