The Revolutionary 7mm Mauser

The Spanish Mauser, firing 7×57mm cartridges, was used with great effect by the Spanish in the Spanish‑American War. It was among the first of a number of late 19th‑ early 20th‑Century conflicts the 7mm Mauser cartridge proved its worth.

If Paul Mauser had not developed this cartridge in 1892, and had Spain not adopted it as their military cartridge a year later, we might not have developed and then adopted the .30–06 in 1906. At the time of the Spanish‑American conflict in 1898, the US Army was armed with the .30–40 Krag cartridge loaded with a 220 grain round‑nose bullet at a muzzle velocity of 2000 fps. The rifle for it by Krag‑Jorgensen had to be loaded a single cartridge at a time, whereas the Spanish troops were armed with Mauser 93, which was loaded from a clip, a much faster method.

At the major battle of the campaign, about 6,500 U.S. soldiers attacked around 750 Spanish defenders in and around San Juan Hill. While the US forces prevailed, they did so at a very high price. About twice the number of defenders were casualties on the US side. Later assessments by US military authorities of the battle results concluded that the reason for the substantial casualties suffered by the US forces was that they were out‑gunned by the Spanish defenders and their Model 93 Mauser rifles chambered for the 7×57mm cartridge. Not long after this finding, the US came out with the .30–03 cartridge and the 1903 Springfield rifle modified soon thereafter to the .30–06 cartridge. Not only was the 7×57 cartridge a proven military round, it was quickly loaded in civilian guise for the sporting market.

Germany found a ready market for their cartridge and Mauser actions in England. Sport hunters quickly learned that the cartridge was a great hunting round. It was an efficient killer of game while delivering very modest recoil to the shooter. The old firm of John Rigby produced a goodly number of their fine rifles for the 7×57, which they chose to call the .275 Rigby. Perhaps its best known proponent was W.D.M. “Karamojo” Bell. John “Pondoro” Taylor reports in his landmark book on African Rifles and Cartridges, that Bell killed 1,011 elephants during his career, “practically all of which he shot with his Rigby‑Mauser of this caliber” (.275 Rigby). Jim Corbett of The Man‑Eaters Kumaon fame, used a .275 Rigby as his #2 rifle. With it, he shot all manners of tigers and leopards in India.

It’s popularity as a sporting cartridge didn’t take long to cross the Atlantic. Most major US rifle manufacturers, sooner or later, chambered rifles in for the cartridge. One of the rarer pre‑64 Model 70 chamberings was for the 7×57.

Outdoor writer icon Jack O’Connor was an early fan of the cartridge. Both he and his wife Eleanor were big fans, but it was Eleanor’s favorite and most used rifle. It was a custom job that Jack had built for himself. Metalsmith Tom Burgess did all the metalwork and Russell Leonard crafted the stock. Eleanor tried the rifle and after having the stock shortened a bit, decided that it had to be hers. She used it for the vast majority of her hunting from then on. She used it to take a 44‑¹⁄₄ inch Dall ram that won a Boone & Crockett medal in 1963. She took it to Mozambique in 1962 and shot seventeen animals with nineteen shots. Jack wrote in his book, The Hunting Rifle, “The only animal that took more that one shot was a kudu bull that didn’t know when it was dead.”

Two 7×57mm cartridges (left) next to 7.5×55 Swiss / GP11 (mid), 308 Winchester and .223 Remington (right).

Jack finally got his own 7×57 chambered rifle a few years later, in 1957, when he contacted Winchester and inquired about a Model 70 in 7×57. The Winchester folks told him that they had exactly one 7mm barrel left and they’d do up a rifle for him. He sent it to Al Biesen who shortened the barrel to 22", stocked it in a nice stick of French walnut, and mounted a Weaver K4 scope in Redfield mounts. He used it on quite a few hunts after that, including taking it to Namibia and Zimbabwe.

The C.I.P established maximum pressure for the cartridge is 56,5565 psi. The SAAMI maximum average pressure is set at 51,000 psi, in deference to the older Mauser still around in that chambering. A modern rifle in that cartridge should be perfectly safe at 60,000 psi. I wouldn’t hesitate to load cartridges at that pressure level for use in my semi‑custom Ruger rifle, or in a custom rifle on a pre‑64 Model 70 action that I once owned but stupidly let get away from me.

The 7×57 has been around for a long time, but even so, the one‑ rifle North American hunter could do far worse than the little 7mm as his/her choice of cartridge provided, the big bears weren’t on the menu. It leaves little to be desired on the table. It is difficult to argue with success and one look at Eleanor O’Connor’s track record with it should be sufficient.

Chapter 3

The Versatility of the .357 H&H Magnum

Box of .375 H&H cartridges with UNI–Classic 300‑gr Bullets. The .375 is one of the most widely utilized cartridges in the world.

The .375 Belted Rimless Nitro Express, better known these days as the .375 H&H Magnum, is a medium‑bore cartridge developed by the renowned British firm of Holland & Holland in 1912 as a one‑upmanship on the Teutonic 9.3×62 cartridge, introduced some seven years earlier.

During the early twentieth century and earlier, many of the European powers were in expansive moods. Africa was one of their major expansion targets to increase their empires. Great Britain, along with Belgium, France, the Netherlands, Portugal, Germany and perhaps another or two, were busy carving out territories there.

One thing these early colonists learned early on was the critters they encountered in Africa were nothing like those inhabiting the hedgerows of Europe and the UK. Africa’s wildlife had many species with the will and capability of biting back in spades. There was an ever‑increasing demand for affordable rifles and ammunition capable of dealing with these animals.

The London and Birmingham gun trade in the UK supplied many such arms and ammo, but the English‑built rifles could hardly be considered affordable by the settling farmers. The majority of the British large bore rifles capable of taking on the dangerous game of Africa at the time, were expensive double rifles, with a few single‑shot rifles thrown in for good measure.

They were, by and large, superb quality rifles, mostly hand‑made, and they and their ammunition were expensive. Otto Bock, a German gun maker, threw a monkey wrench into the English knickers when he introduced the 9.3×62 cartridge in 1905, and chambered many Mauser 98 rifles for this capable round.

The combination of the dangerous game capable cartridge, chambered in the comparatively inexpensive Mauser 98 rifle, was an immediate hit. Shortly after its introduction, most of the British manufacturers set about coming up with their own designs to compete with the Teutonic marvel, including Holland & Holland.

H&H chose a design that featured a rather long case with a long, slow taper. Since the shoulder was pretty small, H&H used a belted case for better headspace control, only the second cartridge to do so.

The powder used at the time was cordite, which consisted of long strands of propellent, rather than granules. The long slow tapered case facilitated the loading process, and contributed to almost fool‑proof feeding and extraction, a big advantage, particularly in tropical climates.

The .375 H&H cartridge (middle) bracketed by the .458 Lott (left) and the .458 Winchester Magnum (right).

The downside is that the cartridge length required a longer length action. It is possible, with substantial machining, to fit the cartridge in a standard length Model 98 Mauser action, but generally it is not a good idea.

If a world‑wide hunter wanted to hunt anything on the planet with but a single rifle, the .375 H&H is one of, if not the best all‑around choice. Commercially loaded ammunition is available just about everywhere, and practically every hunting camp in Africa has at least a box or two around.

It is loaded in primarily two bullet weights, 270 and 300 grains. In the past it was also available in a bullet weight of 235 grains, but I’ve not seen any in decades. I’m not sure it is even loaded in the bullet weight anymore, but that doesn’t matter. The two bullet weights that are readily available everywhere cover the planet nicely.

Jack O’Connor was a great admirer of the cartridge, and used it extensively, mostly on the big cats, lions and tigers. John “Pondoro” Taylor, author of the bible on African Rifles & Cartridges and so titled, raconteur, avid hunter, and highly successful elephant poacher, also thought very highly of the cartridge.

He wrote that one of his rifles in that chambering had accounted for more than 100 elephant and some 411 buffalo, besides rhino, lions and lesser game. He also wrote, “Altho my formula gives this rifle a Knock‑Out value of 40 points, I must regretfully admit that does not really do full justice to it. In actual practice the stopping power of the .375 Magnum would seem to warrant a higher classification.”

Originally a proprietary cartridge loaded exclusively for H&H, they released it to the trade after WWI, and it eventually made its way to the USA. Winchester apparently saw some marketing promise and began manufacturing rifles chambered for it in 1925.

It became quite popular for American safari hunters and also brown bear guides in Alaska, and still is. I currently have three rifles chambered for this magnificent cartridge, and will never be without at least one in my battery.

Actually, largely due to the vast improvements in bullet design and construction, it is a more efficient cartridge today than it has ever been. But then, so are all the rest of today’s cartridges.

Chapter 4