Accurate Cartridges — The .284 Shehane, an Improved .284 Win

If you look at that 5-round group you might think it was shot with a 6 PPC or maybe a 6mmBR. But no, this was done with heavy 180gr Berger Hybrid bullets and the .284 Shehane, an improved version of the .284 Winchester. In fact, this impressive sub-quarter MOA group was shot while fire-forming with a very well-worn barrel!

Gun builder Ryan Pierce of Piercision Rifles explains:

Here’s a 5-shot 0.191″ group at 100 yards with my .284 Shehane fireforming loads. This barrel has 2200 rounds through it. It had 2000 as a straight .284 Win and then I set it back to .284 Shehane to form brass with. This was the first five rounds through it after I cleaned it after the last match. [The load was] 180 Hybrids with 54.0 grains of H4831 SC.

Ya, I figured why not I had some old barrels laying around so I just chopped 2″ off the back and 1″ off the front and chambered it up as a Shehane. Had 1000 pieces to fireform and didn’t want to do all that on a brand new barrel.

My fireform loads are going 2765 FPS. I have a 29″ barrel also though since it’s a setback. Once you get it formed I would push it faster than that or I wouldn’t even bother with the Shehane. My old straight .284 load at 2890 fps had ES spread in single digits for 10 shots. I figured if I get it up to 2935-2950 fps that will be a point or two saved in a several day match.

Fellow .284 Shehane shooter Erik Cortina notes that the .284 Shehane has a velocity edge over the straight .284 Win because it holds more powder: “The Shehane has more capacity than the .284 Winchester. Ryan is using 54.0 grains simply as a fire-forming load. Typical load for a Shehane is around 57.0 grains of Hodgdon H4831 SC.” By blowing the sidewalls out 0.010″, the .284 Shehane picks up about 3.3 grains of extra case capacity. That enhancement makes a BIG difference. The extra boiler room is enough to drive the 180s at 2900-2950 fps with H4831sc, with long barrels.