Friday, March 1, 2013

Modern Loads for a Classic Cartridge

Handloading the .270 Winchester

Being nothing more than a .30-06 Springfield necked down to a 0.277”, the .270 is easy to load.

Story & Photos by James E. House

 I was not around when the .270 Winchester was introduced in 1925, but I became aware of it at an early age.

A well-to-do resident of the small town where I grew up had taken a serious hunting trip to Alaska and some of his trophies were displayed in a local store. That bear was huge but I think I was more impressed with his rifle and the cartridge it fired which were also on display. The rifle was a Winchester Model 70 and the cartridge was a .270 Winchester.

The .270 is still a very popular caliber. The reason is simple: it performs. With a 130-grain bullet having good sectional density and ballistic coefficient driven at over 3,000 ft/sec, the .270 is one of the best choices for medium game at rather long range. Even in comparison to some of the current magnums, the .270 gives up little in this regard.

The .270 is even more versatile with the development of newer high performance bullets. The 140- and 150-grain premium bullets such as the Swift A-Frame, Trophy Bonded Bear Claw, and Nosler Partition make the .270 even more suitable for use on game such as elk than was the case when the cartridge was introduced.

SELECTION OF COMPONENTS

My .270 has not seen a lot of use in recent years. Therefore, I wanted to test it using a range of powders and bullets. To keep the project to a manageable size, I selected five bullets, the 90-grain Sierra hollow point, the 100-grain Hornady spitzer, the 110-grain Sierra spitzer, the 130-grain Sierra Spitzer, and the 150-grain Speer spitzer. Propellants employed were IMR 4064 and 4350, Alliant PowerPro 2000MR and Reloder 17, and Winchester 760. Winchester cases were trimmed to 2.530” and Winchester large rifle primers were used in all loads. Powder charges were weighed to the nearest tenth of a grain. Five cartridges were tested with each load, and they were fired at a target at a range of 100 yards to produce a five-shot group. Velocities were measured at 10 feet from the muzzle using a Competition Electronics ProChrono chronograph.

The load with the 90-grain Sierra hollow point and IMR 4064 gave a five shot group of just over an inch, but four of the shots gave a 0.64” cluster. The 100-grain Hornady driven by 55.0 grains of Reloder 17 gave a very nice group that measured only 0.83”, but four of the shots constituted a group of 0.45”. The four groups with hunting weight bullets averaged almost exactly 1.5” and these loads were not optimized in any way. I believe that with some experimenting and tweaking, even with those loads groups in the 1.2”-1.5” inch range would be obtainable.

The .270 Winchester is even more versatile today than it was half a century ago because of the wide range of bullets available now. Handloading is a way to exploit that versatility. My old Winchester 770 has always performed so well that I have never had the urge to get another .270 Winchester rifle.

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