The .270 Winchester
By Chuck Hawks
Illustration courtesy of Hornady Mfg. Co.
The .270 Winchester is one of the most successful hunting cartridges ever introduced. It shoots as flat as a 7mm or .300 Magnum, kicks less than a .30-06 and kills about as well as either. It is one of the world's greatest all-around hunting cartridges. This blend of desirable characteristics has kept the .270 Win. among the top five best selling cartridges in the USA for decades. It is based on the .30-06 case simply necked-down to accept .277" diameter bullets.
The load that made the .270 Winchester's reputation was a 130 grain spitzer bullet at a muzzle velocity (MV) of 3140 fps. The recoil energy from firing this load in an 8 pound rifle amounts to 16.5 ft. lbs. Although most current factory loaded ammo has backed off a bit on velocity, this level of performance can still be achieved by the reloader.
Today's standard factory loads drive the 130 grain spitzer to about 3060 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. Because the 130 grain .270 bullet is fast, it hits hard. Factory energy figures look like this: muzzle energy (ME) of 2705 ft. lbs., 100 yard energy of 2226 ft. lbs., 200 yard energy of 1817 ft. lbs., 300 yard energy of 1468 ft. lbs., and 400 yard energy of 1175 ft. lbs.
The other classic .270 factory load is a 150 grain spitzer bullet at a MV of 2850 fps and ME of 2705 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.
Here are some .270 specifications that the reloader should keep in mind: bullet diameter .277", maximum COL 3.34", maximum case length 2.54", MAP 52,000 cup.
Most .270 reloaders report excellent results with bullets ranging weighing from 100 grains to 160 grains. The range of 130-150 grains remains the most popular, however. I chose H4831 powder for the examples below because it is widely available, accurate and offers excellent performance in the .270 Win. Other good powders include IMR 4831, IMR 4350, RL-22 and H4350. The .270 is an easy cartridge for which to reload.
The 130 grain bullet is still the most popular with reloaders. For years I used the 130 grain Hornady Interlock SP bullet for my standard .270 handload. The sixth edition of the Hornady Handbook of Cartridge Reloading shows loads with their various 130 grain bullets using 52.3 grains of H4831 for a MV of 2600 fps, to a maximum load of 62.0 grains of H4831 for a MV of 3100 fps. These Hornady loads used Hornady brass and Winchester WLR primers and were tested in a 24" rifle barrel.
The Nosler Reloading Guide, Fifth Edition lists loads for their 150 grain bullets ranging from 51.0 grains of H4831 for a MV of 2728 fps, to 55.0 grains of H4831 for a MV of 2905 fps. The 150 grain Partition spitzer bullet is a proven favorite for tough game like North American elk. The Nosler loads mentioned above were developed using Winchester cases and Federal 210 primers; they were chronographed in a 24" rifle barrel.
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 Hodgdon Data Manual, 26th Edition this bullet can be driven to a MV of 2434 fps by 51.0 grains of H4831, or a MV of 2581 fps by a maximum load of 54.0 grains of the same powder. 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!
Note: A full length article about the .270 Winchester can be found on the Rifle Cartridge Page.