The Reign of the Weatherby Mark V Part II

To be honest, there was never a time when I didn’t want to own a Weatherby Mark V, but there have been times when I couldn’t afford one. Still, I’ve managed to purchase them from time to time because they represent something special in fit, finish and performance. Fortunately, as the price of Remington and Winchester firearms climb sharply, two thousand dollars for a slick Weatherby Mark V Deluxe is beginning to look like a bargain. FN Winchester’s plain Model 92 Trapper is priced at $1,200, a firearm that sold near the $300 mark just a handful of years ago. Much of Remington’s custom shop catalog is comprised of standard models of years past that have been relegated to “build on demand” status. No special components or finishing touches, yet many sell for twice the price of the Weatherby Mark V Deluxe.

The 378 Weatherby Magnum and the myth of recoil…

The folks who describe the recoil of a 378 Weatherby as nearly nuclear never cease to amaze me. Even Craig Boddington, one of my favorite authors, wrote in his book Safari Rifles that he had no shooting experience with a 378 Weatherby Magnum, but “When you get 2,900 fps with a 300 grain bullet, you’re starting to pay a vicious price in recoil”. Then he went on to offer no such critique of numerous bigger bore guns with heavier bullets and significantly greater recoil.

A scoped Mark V 378 Weatherby Magnum weighs approximately 10 pounds. A 300 grain bullet moving at 2,900 fps, charged with 112 grains of powder, produces 62 ft/lbs of recoil. In a rifle of similar weight, the 416 Rigby, pushing a 400 grain bullet to 2,400 ft/sec, generates 70 ft/lbs of recoil. A 458 Lott pushing a 500 grain bullet to 2,300 fps generates 83 ft/lbs of recoil. The 378 Weatherby Magnum, in non-emotional, non-sensationalizing terms, has moderately more recoil than a typical rifle chambered for the 375 H&H. With a very efficient Weatherby Accubrake in place, recoil is cut in half. The next time someone defines the 378 Weatherby Magnum’s recoil as extreme, ask them how many times they have actually pulled the trigger on a 378 Weatherby Magnum, then ask for proof.

Feeding a 378 Weatherby  Magnum…

Weatherby ammunition is manufactured by Norma Precision AG. Very high quality raw material, process and components.  Weatherby offers four types of ammunition for the 378 Weatherby Magnum: 270 grain Hornady soft point, 270 grain Barnes TSX, 300 grain Hornady round nose expanding, and 300 grain Hornady full metal jacket. The price for all is $142/20, with the exception of the Barnes load, which is $164/20. Purchasing through leading discount retailers saves approximately $10 – $18 per box.

Handloading 378 Weatherby-based cartridges can result in precisely assembled ammunition, optimal component selection and much more shooting per cubic dollar. These days, reloading die cost is about the same as standard cartridges. Total component cost is as little as $30 per 20 rounds, which is actually 20% – 25% less than comparatively premium quality, but wimpy, 300 WSM factory ammunition. New brass runs $84/20 when purchased through Weatherby and $78/20 through discount retailers. With annealing, it is reasonable to expect the brass to survive five reloads, six cycles of use, which makes the effective prices for 20 pieces, respectively, $14.03 and $13.00.

Shooting Weatherby cartridges requires a little more thought than other rounds when it comes to bullet selection. While the Weatherby’s higher velocity extends the distance at which a bullet will reliably expand, closer in, a bullet must perform at an elevated impact velocity. Selection used to be a simple matter of checking the manufacturer’s impact velocity specifications for its bullets, but much of that information is now withheld or just not credible as published. i.e. manufacturers listing minimum impact velocity as 1,800 fps and maximum listed as unlimited. The seven bullets pictured above are what I routinely use for higher performance .375 caliber handloads.

The Barnes Triple-Shock 235 grain is the only bullet of this light weight, that I am aware of, that can handle 3,300 fps, expand properly and retain most of its weight on impact. Too light for my personal taste, but it is recommended for elk and animals of similar weight with the 378 Weatherby Magnum.

Swift A-Frame bullets, #2 (250 grains), #3 (270 Grains and #6 (300 grains) are all good flying and super tough bullets. Compared to a Nosler Partition the Swift has a much thicker bridge and jacket all the way up through the ogive and to the tip. The soft lead tip is protected from recoil damage by what is referred to as a protected point construction; lead flush with the jacket. Any 378 Weatherby Magnum recovered bullets I’ve seen were mushroomed to the bridge, the shank was intact and mid to high 90% of its weight was retained. They tend to penetrate well.

My problem with Swift bullets, in the past, had been price. Fortunately, while much of the bullet making community has ratcheted up prices commensurate with the rising price of gold, Swift prices have pretty much remained stabile over the past few years.  At $1.20 or so per bullet, they are inexpensive insurance when hunting big and dangerous game.

The 285 grain Speer Grand Slam, #4, is another tough bullet, but with a one piece bonded core. The one piece lead core makes for high sectional density and relatively short length. The Grand Slam at 285 grains is the same length as the all copper Barnes 235 grain bullet. The Grand Slam,  with a  0.354, B.C. makes for relatively flat shooting. Price is approximately the same as the Swift A-Frame.

The 300 grain Sierra bullet, #5 above, has a good ballistic coefficient for increased retained velocity. It does not have the heavy construction of some of the other bullets, but its 300 grain weight sets velocity at a reasonable 2,900 fps or so. Sierra recommends this bullet for longer distance shooting and for use on large African plains game. I like them for range proficiency shooting because they are inexpensive as .375 caliber rifles go. At 60¢ a bullet, they are half the price of the other bullets listed.

Woodleigh #7 Australian made Woodleigh bullets are very nicely done. With lots of experience with big and dangerous game bullets, including some of the more exotic express rifle cartridges, they do make an excellent product. In this case, I reserved them for the heavy for caliber 350 grain loads where the protected point version has a good BC and without much of a bullet length penalty over a 300 grain bullets.

I realize I have referenced bullet length several times, but only because it is an important issue, even with cartridges like the 378 Weatherby. Shorter bullets are easier to stabilize at standard rifling twist rates and shorter bullets eat up less case capacity. A 300 grain lead core Speer bullet, seated to the maximum cartridge overall length, saves eight grains of powder capacity in comparison to a 300 grain Barnes Triple Shock of the same weight and maximum cartridge overall length.  Even with its huge capacity, the 378 Weatherby Magnum loads listed below are almost all case full of very slow smokeless powder.

Powder selection

While most .375 caliber cartridges are loaded with powder more consistent with the .30-06 Springfield, the 378 Weatherby Magnum is not. Where the 375 H&H is comfortable with Alliant’s Re 17, the 378 Weatherby Magnum is better filled with Re 22. The 378 Weatherby Magnum rates a 23.3 on the Real Guns Barrel Burner Index, and expression of the proportional relationships that exist within cartridge capacity, pressure and bore capacity. The index number for the .375 H&H is 15.7, 20.9 for the 257 Weatherby Magnum and 28.4 for the 30-378 Weatherby Magnum. This means that if you use a 378 Weatherby Magnum for varmint hunting, chances are you will have to rebarrel in 4,000 – 5,000 rounds. Yes, that was sarcasm. Thank you for noticing.

A note on primers – I did load Federal #215 primers along side CCI #250 primers and there was no measurable difference within statistically typical velocity spread.

Rule #1 – It’s good to measure stuff

Weatherby lists the freebore for the Mark V 378 Weatherby Magnum as 0.756″. For all of the handloads that follow, each listed bullet was double checked for clearance with a Hornady COL gauge and assembled cartridges were checked with an adjustable Wilson Cartridge Case Gage.

With the exception of the Sierra 300 grain GameKing, which does not have a cannelure, COL was established by referencing the location of the respective bullet’s cannelure and associated SAAMI, reloading manual or manufacturer’s published COL specification. The exception, once again, is the Sierra bullet that is listed in Sierra’s Edition V manual with a 3.680″ COL, which is longer than SAAMI maximum length. COL was held to SAAMI spec and powder charges were appropriately reduced.

Warning: Bullet selections are specific, and loads are not valid with substitutions of different bullets of the same weight. Variations in bullet material and length will alter net case capacity,  pressure and velocity results. Primer selection is specific and primer types are not interchangeable. These data represents maximum loads in our firearms and test equipment and may easily be excessive in other applications. All loads should be reduced by 3%,  and developed following safe handloading practices as represented in established reloading manuals produced by component manufacturers. Presentation of these loads does not constitute a solicitation for their use, nor a recommendation.

The Weatherby rifle is a bit of a Ferrari; people sometimes don’t see the well engineered, high performance firearm beneath its glossy surface. The Weatherby Mark V has been precisely built to perform well; accuracy, durability and shooter comfort, with high intensity Weatherby cartridges.

During the final shooting session, the gun’s muzzle stayed down under recoil. As long as I held my concentration and ignored the muzzle blast during extended live fire, the Weatherby delivered more than might be expected from a big cartridge of this type.

Shooting from a standing position the rifle felt balanced and comfortable in hold. I like the shape of the hand filling forearm and pistol grip. For a simple, compact recoil pad, the Decelerator is still one of the best.

While the rifle is slick in appearance, bright bluing and gloss finished walnut, it is not in the least bit fragile or prone to handling marks, scrapes or scratches and the bluing wipes clean easily.

While the Mark V and 378 Weatherby Magnum make for an excellent dangerous game killing combination, each is available within other combinations. The Weatherby Mark V is available in fourteen chambers, with a variety of synthetic and walnut stocks and metal finishes, with prices ranging from $1,600 for guns that can be found at your local retailer to tens of thousands of dollars worth of firearm art that can be purchased through the Weatherby Custom shop.

For the hunter who wants the power of the 378 Weatherby Magnum in a different package, Weatherby offers rifles with both more upscale features and others with more utility features. The Dangerous Game Rifle is optimized for hunting; tough synthetic stock, metallic sights, extra magazine capacity, and matte finish. The Royal Ultramark has an exhibition grade walnut stock, engraving and gold and French gray nickel inlays that would be something special for anyone to own. Stop in at theWeatherby site where all models and associated prices are covered in great detail.

The Reign of the Weatherby Mark V Part I
The Reign of the Weatherby Mark V Part II