The Great .270 Winchester
By Chuck Hawks
Illustration courtesy of Hornady Mfg. Co.
The .270 Winchester is regarded by many experienced experts as one of the best all-around cartridges for thin-skinned non-dangerous game. Jack O'Connor used the .270 almost from the beginning, and wrote extensively about it throughout his long and illustrious career. He probably did more than any other single person to popularize the .270. It is certainly on my short list of four great all-around cartridges. (The other three are the 7mm Rem. Mag., .308 Win. and .30-06 Spfd. See my article "All-Around Rifle Cartridges" for more on this subject.)
Almost from its introduction the .270 established itself as a premier long range hunting cartridge; its evolution into, and its acceptance as, one of the 4 or 5 most versatile cartridges in the North America probably surprised even Winchester. It has proven effective on everything from jackrabbits to elk, and is in regular use in all the game fields in the world. It is more than needed for jackrabbits and a bit light for elk, but it has and will take both with appropriate bullets and well placed shots.
Introduced in 1925 by Winchester, the classic .270 is based on the .30-06 case necked down
to take .277 inch diameter bullets (.270 inch is the bore diameter, not the bullet diameter).
Considered somewhat "over bore" when it came out, .277 turned out to be just about the
optimum diameter bullet for the capacity of the .30-06 case and modern powders. The .270 has
earned a reputation for excellent accuracy with all weights of bullets from 100 grains to 180 grains. Most .270's will even group the common 130, 140, and 150 grain bullets into approximately the same place at 100 yards, which is unusual among rifle calibers.
The .270 is one of the most imitated calibers of the 20th Century. The list of cartridges designed to approximate, equal, or exceed the .270's performance includes several factory loads and numerous wildcats (which I don't have the space to mention here). One of the more notable efforts is the .280 Remington, the .30-06 case necked down to take .284 bullets, and designed to challenge the .270 as an all-around cartridge. Others include the .284 Winchester (Winchester's attempt to offer .270 ballistics in short action rifles), the 6.5mm Rem. Mag. (Remington's short magnum designed to do the same thing), the .270 WSM (a short but very fat magnum designed to exceed the performance of the .270), and the .270 Weatherby Magnum (which actually does exceed the performance of the .270).
None of these cartridges has come close to the .270 Winchester in popularity, of course. The .284 Win. is dying and the fine 6.5 Rem. Mag. is available only from that company. The .270 Wby. Mag. is chambered only by Weatherby. The .280 Remington has become moderately successful
after a very slow start, but has never approached the .270 in sales.
Compare this to the .270: virtually every major ammunition manufacturer in the world, on every continent where game animals are hunted, loads for the .270, and almost every rifle maker with an action long enough and strong enough to handle the .270 chambers for it. Look in the Shooter's Bible reference pages where they list the rifle models made for each of the cartridges, and it is plain that the .243 Win., .270 Win., 7mm Rem.Mag., .308 Win., .30-06 Spfd., and .338 Win. Mag. are by far the most popular cartridges with the rifle makers. One might conclude that these are also pretty popular with rifle buyers. By any measure--ammunition sales (where it ranks third), new rifle sales, or reloading dies sales--the .270 Win. is one of the most popular centerfire rifle cartridges on earth. Along with the .308 Winchester and .30-06, .270 cartridges can be purchased virtually anywhere that ammunition is sold. This is an important consideration for those who hunt far from home.
The load that made the .270's reputation was a 130 grain spitzer bullet at a muzzle velocity (MV) of 3,140 fps. The recoil energy from firing this load in an 8 pound rifle amounts to about 16.5 ft. lbs. This level of performance can still be achieved by the reloader. Today's standard factory loads drive the 130 grain spitzer to about 3,060 fps. The Speer 130 grain flat base spitzer has a ballistic coefficient (BC) of .408, and a sectional density (SD) of .242; the 130 grain boat tail spitzer has a BC of .449. These numbers are right in the big game ballpark. And because the 130 grain .270 bullet is fast, it hits hard. Factory energy figures look like this: muzzle energy (ME) of 2,705 ft. lbs., 100 yard energy of 2,226 ft. lbs., 200 yard energy of 1,817 ft. lbs., 300 yard energy of 1,468 ft. lbs., and 400 yard energy of 1,175 ft. lbs.
These figures show that the .270 hits as hard with a 130 grain bullet as the .308 Winchester does with a 165 grain bullet at all ranges. (A .30 caliber 165 grain bullet has a similar sectional density to the .270 caliber 130 grain bullet.) The .30-06/165 grain bullet hits a little harder than the .270/130 grain bullet at the muzzle, but at 400 yards they are almost even. And the .270 definitely shoots flatter than either of its .30 caliber rivals. According to Remington figures, at 300 yards the .270/130 grain bullet has about 1.7 inches less drop than the .30-06/165 grain bullet, and about 1.9 inches less drop than the .308/165 grain bullet.
I am comparing the .270 to the .308 Win. and .30-06 because these are the consensus choices as best all-around standard rifle cartridges. The loads I am comparing are the most similar in trajectory, energy, and penetration. But it is also worth noting that the .270/130s trajectory is almost identical to that of the popular 7mm Mag./150 and .300 Mag./180 bullets.
Zero a scoped .270 shooting a 130 grain spitzer bullet with a BC of .408 at 3,150 fps to hit 3 inches high at 100 yards and the path of the bullet is as follows: +3.3 inches at 200 yards, -1.1 inches at 300 yards, -3.1 inches at 325 yards, and -11.2 inches at 400 yards. This means that no hold over is required to put a bullet into the heart-lung area of an animal the size of a small deer or antelope at 325 yards. Since the drop at 400 yards is only 11.2 inches, a hold at the top of the back would insure a solid hit on a mule deer size animal even at that range.
The other classic .270 factory load is a 150 grain spitzer bullet at a MV of 2,850 fps and ME of 2,705 ft. lbs. This load can also be duplicated by reloaders, and the Speer 150 grain flat base spitzer bullet has a ballistic coefficient of .481 and a SD of .278. The sleek 150 grain boat tail bullet has a BC of .496.
The 150 grain factory load drops only about 1.2 inches more at 300 yards than the 130 grain bullet, which means that it still shoots flatter than either the .308 or .30-06 with 150 grain bullets, and the energy figures for the .270's 150 grain bullet are within a few foot pounds of the .270's 130 grain bullet at all ranges. The difference is that the .270's 150 grain bullet has a SD comparable to the 180 grain .30 caliber bullet. The .270/150 grain bullet penetrates as well as a .30/180 grain bullet of identical construction. It is usually recommended for large animals like North American elk or Scandinavian alg (moose).
A relatively new factory load for the .270 Winchester is the 140 grain spitzer bullet. Federal loads this bullet to a MV of 3,100 fps. The other major loading companies advertise MV's from about 2,925 to 3,050 fps. I have never used 140 grain bullets in a .270, but they appear to be very effective loads. Using one of the Remington offerings as an example, it uses a Nosler Ballistic Tip Bullet at a MV of 2,960 fps and ME of 2724 ft. lbs. This bullet is traveling 107 fps faster and shooting .1 inch flatter than the standard 130 grain factory load at 300 yards and developing about 273 ft. lbs. more energy than either the 130 grain or 150 grain bullets at that range.
The BC of the Nosler Ballistic Tip 140 grain spitzer is .456, the SD is .261. This SD is very similar to the Nosler Ballistic Tip 7mm 150 grain spitzer (.266), and quite a bit better than the Nosler Ballistic Tip .30 caliber 165 grain spitzer (.248). According to the fifth edition of the Nosler Reloading Guide 49.5 grains of IMR 4831 will drive their 140 grain bullets to a MV of 2670 fps; 53.5 grains of IMR 4831 will drive the same bullets to a MV of 2910 fps. For larger, tougher animals at extended range, these 140 grain loads for the .270 Win. are probably about as good as it gets.
The 130 grain bullet is still the most popular with reloaders. The Nosler Reloading Guide shows loads with H4831sc from 55.0 grains at a MV of 2909 fps to 59.0 grains at a MV of 3124 fps with their 130 grain bullets.
Nosler lists loads for their 150 grain bullets ranging from 51.0 grains of H4831 and a MV of 2728 fps to 55.0 grains of H4831 and a MV of 2905 fps. The 150 grain Partition spitzer bullet is a proven favorite for tough game like North American elk.
All of the Nosler loads mentioned above were developed using Winchester cases and Federal 210 primers; they were chronographed in a 24" rifle barrel. I chose various incarnations of #4831 powder for these examples because it is usually very accurate and offers good performance in the .270; #4831 is often regarded as the powder for .270 Winchester loads.
Bullets heavier than 150 grains are available to the reloader who fancies them. The heaviest bullet for the .270 that I know of is the Barnes 180 grain Original. According to the Barnes Reloading Manual this bullet can be driven to a MV of 2,743 fps; muzzle energy should be about 3,000 ft. lbs. Barnes also makes another interesting .277 inch bullet, the 150 grain RN solid. This completely non-expanding bullet would be just the thing if you had to shoot through an armored car with your .270!