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Reloading .270
The .270 Winchester is perhaps one of the most successful
hunting cartridges ever introduced. It shoots as flat as a 7mm or .300 Magnum, has
less recoil than a .30-06 and has plenty of stopping power for just about any
North American game. This blend of desirable characteristics has kept the .270
Win. among the top five bestselling cartridges in the USA for decades.
Essentially, it is based on the .30-06 case that has been
necked-down to accept .277" diameter bullets. The load that gave the .270 its
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. It
makes it better that the .270 is one of the easiest calibers for reloading
brass.
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. Since 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.
The 130-grain bullet is still the most popular with
reloaders. 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!
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