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June 2nd, 2019

.284 Shehane — Winning Wildcat for F-Open Competition

7mm .285 shehane improved f-class f-open caliber cartridge chambering

High-BC 7mm Bullets 7mm (.284) remains the caliber to beat in F-Class Open Division (though some shooters have had success with .30-Cal short magnums.) With a standard .284 Winchester, or better yet, a .284 Improved, you can drive the high-BC Berger 180gr and 184gr bullets to competitive velocities.

The straight .284 Win is an excellent cartridge, quite capable of winning F-class matches. However, in most barrels, it can’t push the 180s at 2900-2950 fps velocity levels*. A lot of barrels will top out at about 2850 fps. That’s where the .284 Shehane comes into play.

The .284 Shehane is a slightly modified wildcat that retains the same 35° shoulder as the parent case. However, 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 N560 or Reloder 17 you can go even faster.

Norm Harrold Won 2018 F-Class Open Division Nationals with .284 Shehane Rifle
F-Class Open F-Open Norm Norman Harrold Champion Championship 2018 Raton NM New Mexico 284 Shehane Berger Bullets

Norm Harrold (above) won the 2018 USA F-Class Nationals shooting a .284 Shehane. Norm’s F-Open rig features a McMillan Kestros ZR stock and Bartlein barrel chambered for the .284 Shehane, which has a bit more case capacity than a standard .284 Winchester. Norm loaded Berger 184gr 7mm bullets in Lapua brass. Norm revealed his load in an Erik Cortina YouTube Video.

F-Class 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.

Forum member Jim Hardy has shot the .284 with great success. He tells us: “In my humble opinion, the .284 Shehane is the best balanced long-range round there is — bar none. Here is why:

You have to shoot a 30 Cal Magnum with a 240gr bullet to equal the performance of most 7mm chamberings with the 180 Berger VLD. With the .284 Shehane, you have a .308 bolt face, medium action, and Lapua brass. You use less powder than the 7 mags, and have great accuracy and ballistics even while fire-forming. The .284 Shehane shoots inside the 6.5 AND the straight .284, the .300 WSM, and the .300 Win Mag with less recoil. What is not to love about the 284 Shehane? It is a no-brainer for long range — F-Class or Prone or 1000-yard Benchrest.”

Scotland’s Grant Taylor. who used the .284 Shehane to finish third at the 2009 F-Class Worlds in England says the .284 Shehane is “very accurate with superb vertical spreads at 1000 yards. [This] caliber… has awesome accuracy. I’m getting 2930-2950 fps with spreads in the 3-5 fps range. I use Hodgdon H4831sc powder, CCI BR2 primers, and pointed 180gr Bergers.”

.284 Shehane Shines in 1K Benchrest Competition Too
The .284 Shehane has won in Benchrest as well as F-Class competition. In 2013, Henry Pasquet won the IBS 1000-Yard Nationals shooting a .284 Shehane. Henry’s Championship-winning rig is shown below. Note the 5″-wide fore-end which is not legal for F-Class. Henry also runs a combo tuner/muzzle-brake.

.284 Shehane Henry Pasquet ibs 1000 yard championship

Amazing Accuracy When Fire-Forming .284 Shehane

7mm .285 shehane improved f-class f-open caliber cartridge chambering

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. 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. [The load was] 180 Hybrids with 54.0 grains of H4831 SC.”

*Some exceptional barrels chambered in straight .284 Win can reach 2900 fps with the 180s. Ryan Pierce has a 32″ Brux barrel that is delivering 2900 fps with the straight .284. However, Ryan acknowledges that his velocities are not typical: “A lot of .284 Win barrels top out at around 2850 fps with the 180s”.

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April 22nd, 2016

IMR® Powders introduces IMR 4955 Enduron Powder

In 2015, IMR® Powder introduced a new line of powders with Enduron® Technology. These powders are designed to address several performance gaps as powder technology has advanced. Here are key features of the Enduron line of propellants:

Enduron powders contain an additive that drastically reduces copper fouling in the gun barrel. Copper fouling should be minimal, allowing shooters to spend more time shooting and less time cleaning a rifle to retain accuracy.
The new Enduron line is insensitive to temperature changes. Whether a rifle is sighted in during the heat of summer, hunted in a November snowstorm or hunting multiple locations with drastic temperature swings, point of impact with ammunition loaded with Enduron technology will be very consistent.
Enduron powders provide optimal load density, assisting in maintaining low standard deviations in velocity and pressure, a key feature for top accuracy.
Enduron technology is environmentally friendly, crafted using raw materials that are not harmful to the environment.

New IMR 4955 for Larger Cartridges
For 2016, IMR has introduced IMR 4955, a new Enduron extruded powder that is a top performer with popular cartridges such as 270 Winchester, 25-06 Remington, 280 Remington, 300 Winchester Magnum and many more. This new powder falls directly between the new IMR 4451 and IMR 7977 in burn speed, providing excellent performance for most big-game cartridges. Like all Enduron Technology powders, IMR 4955 is temperature insensitive, as shown below.

Hodgdon IMR Enduron 4955 temperature stable powder reduced fouling

Adding this propellant to the Enduron line filled in an important place on reloading benches. IMR 4955, plus the original three Enduron powders, provide excellent loading solutions for cartridges from 223 Remington to the massive 500 Nitro Express Magnum. Further, in these days of powder shortages, these new Enduron powders can fill a gap by providing comparable performance to select Hodgdon® powders. Specifically, IMR 4955 is a great choice for cartridges that work well with Hodgdon H4831.