The .270 Winchester is perhaps the most storied big game hunting cartridge. While the .30-06 Springfield enjoys praise for both the contribution it made to the United States’ military efforts and as a hunting cartridge, the .270, on the other hand, exists for one purpose—to put game in the freezer. It has no martial pedigree.
Why has the .270 received such coverage and hyperbole? After all, it doesn’t generate the awesome energy figures associated with the big magnums, and while it’s popular to a degree, it doesn’t have the innumerable fans who are devoted to the .308 Winchester, .30-06, or 7mm Remington Magnum.
The .270 appeals to a certain hunter; one who understands the finer points of ballistics. One who appreciates balance. The .270 is to hunting cartridges what the Porsche 911 is to cars: focused, precise, controlled, and when needed, violent and powerful.
In the Beginning
Winchester introduced the .270 in 1925. A gutsy decision. World War One had ended less than a decade prior. American men by the millions served in their nation’s military during the conflict. There they met and fell in love with, the .30-06. When they returned to civilian life, they wanted to hunt with the round they had become so familiar with during their service days. At the time, the .30-30 Winchester ruled the roost as the country’s premier deer cartridge, and hunters could buy inexpensive, surplus rifles such as Spanish and Swedish Mausers chambered in 7x57mm and 6.5x55mm. The .270 faced a competitive marketplace filled with hunters who needn’t look elsewhere for a good round.
The Winchester Repeating Arms Company wanted a proprietary, flagship cartridge to usher in their newest flagship rifle, the Model 54—a Mauser derived, bolt-action sporter. The marketing mavens in New Haven, Connecticut had hyped the Model 54 as the last word in modern firearms and promised customers a new standard in accuracy and reliability. While the rifle hit a home run and would father the Model 70, the .270 cartridge languished. At best a mid-pack item, at worst, a sluggish seller. Winchester debated whether to show their brainchild the door.
Go West, Young Man
The .270’s competitors mentioned above were too well entrenched in hunters' minds during the 1920s and '30s. Entrenched in the Eastern and Southern U.S., where most people lived at the time. Eastern hunters knew their craft. They stalked through dense forests, marshes, and wide, flat river valleys. Seldom did a hunter there shoot more than 100 yards to drop a whitetail deer, or perhaps a moose. They didn’t need the .270.
Not so in the West, though. While this vast land held far fewer people than back East, those who lived and hunted there knew one thing: they needed something with long legs. All too often, western hunters could see mule deer, elk, or bighorn sheep, but they couldn’t touch them. Those critters would loiter atop high buttes or far-off ridges confident no human could get within four or five hundred yards without detection. Never mind working in close enough for a shot with a .30-30 on a nervous pronghorn on the wide, flat prairies. They’d spot a hunter miles off with those eight-power binoculars called eyes and bolt over the horizon at sixty miles per hour. Frustration dogged western hunters day in and day out. There had to be a better way, they thought.
A Man From Nogales
Into this environment walked a young man who liked to hunt bighorn sheep. Born in 1902, Jack O’Connor grew up in dusty little Nogales, Arizona. He learned to hunt at an early age, as did most boys in the West back then. The .270 hit the market when Jack turned twenty-three. He’d heard about the new round, how it shot flat as a Kansas prairie and hit like a .30-06, but he had other guns and not much money. Life too had many demands. Jack finished college, got married, and struggled to support the new family as a writer
In 1939, Jack’s work caught a magazine editor’s attention. Not just any magazine; Outdoor Life, the premier hunting and adventure periodical in America. Jack would go on to make his mark at the magazine and publish many books during a career that spanned over forty years.
Jack loved rifles, and somewhere along the line between college and the Outdoor Life gig, he picked up a .270. At last, Jack had found the western hunter’s dream gun. He marveled at how well it could ruin a far-off, haughty deer or elk’s day. Jack never hesitated to share the .270’s virtues with his readers.
Back at New Haven, the Winchester execs noticed their sleepy little .270 cartridge’s sales had blossomed. In just a few decades, it rivaled the .30-06, a position it wouldn’t relinquish until Winchester itself upset the apple cart in the 1950s and '60s with their mainstream magnums based on a .30-06-length, .375 H&H case.
By such time, though, even eastern hunters had fallen for the .270, and its place in the hunting cartridge pantheon became assured.
To understand why the .270 is such a good, and popular, cartridge, one needs to understand its technical attributes.
While it is considered a .30-06 family member, the .270 Winchester is, in fact, based on the .30-03 cartridge case. The .30-03 is the .30-06’s father and its case is 1.5 millimeters longer.
Winchester had a sound reason to not just neck down the .30-06 and get on with things. The smidge longer .270 case prevents its use in .30-06 rifles. Something which could have catastrophic results. Later, in 1978, Remington based the .270’s nearest rival, the .280 Remington, on the .30-03 case for the same reason.
The .270 is unique among sporting rifle cartridges. It uses a .277 caliber diameter bullet. Winchester’s records are unclear why their engineers selected this odd-ball size given they could have used more common .264, .284, or .308 bullets. Perhaps they watched as the U.S. army experimented during the 1920s with the .276 Pederson (6.8x51mm) cartridge as a replacement for the .30-06, and saw the theoretical advantages these bullets possessed.
The .277 caliber bore size is an attractive compromise between the efficient, but narrow .264 and the less efficient, but heavier and wider .308. They give an ammunition designer higher ballistic coefficients and sectional densities, weight for weight, than the .308 along with wider wound channels than the .264.
Winchester wanted a cartridge that would appeal to hunters in the West and plains states. To do this, they need to improve—to “flatten”—the benchmark .30-06’s trajectory. Hunters at the time still used iron sights, for the most part. Scopes continued to improve in quality, but they did not have reticles the user could adjust for range and wind as with modern optical sights. A shooter back then had to guess as to how far above the desired point of impact to hold the sights on a target for a given range.
If Winchester could give these hunters a round that hit within a six to eight-inch circle beyond 250 yards, it would eliminate the guesswork needed for long shots, and hunters would beat a path to the company’s door. The .270 fit this requirement because, while its case had the same rough powder capacity as the .30-06, it fired lighter, higher BC bullets. This generated faster velocities which meant not just a flatter trajectory but also greater impact energy on target at those extended ranges. The lighter, more efficient .277 caliber bullets retained speed downrange better than the .30-06 and their higher SDs let them drive deep into animals like a 6.5mm bullet. Who could ask for more?
.277 caliber bullets come in weights from 95 to 180 grains. The most common, though, are 110, 130, 140, and 150 grains. The lightest bullets, 110 grains and under, are intended for varmints such as coyotes and foxes. The 130 and 140 are great for deer-sized animals, with the 130 reputed as the deer hammer. The heavier slugs, 150 on up, are fit for large game such as elk, moose, and black bear, or are ultra-high BC projectiles for long-range, precision shooting.
Factory nominal muzzle velocities for the most common bullet weights are as follows.
- 130 grain: 3060 fps
- 140 grain: 2950 fps
- 150 grain: 2850 fps
Since muzzle energy is almost equal between the various weights, the deciding factor on which to use for what game is sectional density. The higher the SD, the deeper the bullet will penetrate. This efficiency allows a .277 caliber bullet to cause similar wounds as a .308 caliber which weighs ten to twenty grains more. The .270 does this with less recoil than the .30-06.
While the same general rule applies when .264 caliber (6.5 mm) bullets are compared to .277 caliber, the .277s greater initial diameter creates a wider wound channel, if all other factors are equal.
Bullets for the .270
Here is a BC (G1) and SD comparison between .277, .264 and .308 caliber spitzer boat tail bullets in the most popular weights for each.
- 130 grain: .435 BC, .242 SD (Nosler AccuBond)
- 140 grain: .496 BC, .261 SD (AccuBond)
- 150 grain: .496 BC, .279 SD (Nosler Ballistic Tip)
- 130 grain: .488 BC, .266 SD (AccuBond)
- 140 grain: .509 BC, .287 SD (AccuBond)
- 150 grain: .435 BC, .226 SD (AccuBond)
- 165 grain: .475 BC, .248 SD (AccuBond)
- 180 grain: .507 BC, .271 SD (AccuBond)
A 150 grain, .277 bullet has a BC comparable to both a 140 grain, .264 and 180 grain, .308. Its SD splits the difference between the other two competitors, and all three are considered effective on large, thin-skinned game. When it comes to deer bullets, Jack O’Connor’s favorite, the 130 grain .277, has the same BC as the classic 150 grain .308, but a superior SD. Although, the 130 grain .264 beats them both, the larger two will make a wider wound channel.
The standard 130 grain .270 load has excellent exterior ballistics. Many experts consider 1200 ft-lbs. the minimum energy for humane kills on medium-sized game. The 130 grain delivers this at 500 yards, perfect for mule deer or pronghorn. This load’s nominal MPBR for a six-inch vital zone is 305 yards (!) when zeroed at 257 yards.
Here are the velocity, impact energy, bullet drop with a 200-yard zero, and wind drift in a 10-mph crosswind out to 500 yards adjusted for standard atmosphere at sea level.
- Muzzle: 3060 fps, 2703 ft-lbs., 0 inches, 0 inches
- 100 yards: 2839, 2327, + 1.41 inches, 0.69 inches
- 200 yards: 2629, 1996, 0, 2.76
- 300 yards: 2429, 1704, -6.46, 6.41
- 400 yards: 2237, 1445, -18.82, 11.8
- 500 yards: 2055, 1219, -38.15, 19.18
The 140 grain load makes medium game energy at 570 yards, and has a 295-yard MPBR with a 250-yard zero. It delivers more energy and less drift than the 130 grain for just an inch more drop at 400 and 500 yards. Impressive. Here are the numbers with a 200-yard zero.
- Muzzle: 2950, 2705, 0, 0
- 100 yards: 2761, 2369, +1.55, 0.64
- 200 yards: 2579, 2068, 0, 2.53
- 300 yards: 2405, 1798, -6.75, 5.83
- 400 yards: 2237, 1556, -19.54, 10.7
- 500 yards: 2076, 1341, -39.3, 17.3
When it comes to large game, the 150 grain load is the classic choice for the .270. The minimum recommended energy for elk is 1500 ft-lbs., and the 150 grain delivers this at 415 yards. MPBR is 285 yards on a 242 yard zero. Trajectory and drift are close to a 180 grain .30-06, but the .270’s greater SD means it should penetrate deeper. The 200-yard zero figures look like this.
- Muzzle: 2850, 2705, 0, 0
- 100 yards: 2665, 2366, +1.71, 0.67
- 200 yards: 2487, 2016, 0, 2.65
- 300 yards: 2316, 1788, -7.34, 6.13
- 400 yards: 2152, 1543, -21.18, 11.25
- 500 yards: 1995, 1326, -42.53, 18.21
The Final Word
The .270 is an honest cartridge. It just does what it says without fuss or bother. It shoots flatter than a .30-06 and hits almost as hard. All with five foot-pounds less recoil, on average, than its bigger brother. The latest low-drag, long-range bullets will extend this classic’s performance envelope into magnum territory, again with lower recoil. It will drop any North American game animal, except perhaps the big bears and bison, and Jack O’Connor loved it for the African plains game.
There are many cartridges these days that will outdo the .270 Winchester, but they beat up the shooter and ammunition is often expensive and scarce.
The .270 is James Bond in a brass suit—smooth, sophisticated, pinpoint accurate, and deadly. It’s everything a hunter needs in a rifle cartridge and nothing they don’t. No wonder it is so popular and loved around the world.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
© 2018 LJ Bonham