.375 H&H Magnum
Encyclopedia
The .375 Holland & Holland Magnum is a powerful rifle
round and one of the best-known and most popular medium-bore
cartridges in the world. The .375 H&H was only the second cartridge ever to feature a belt, now common among magnum rounds. A popular misconception is that the belt is for headspace, with some saying it is due to the narrow shoulder. However, many cartridges with much smaller shoulders and greater taper have no belt at all and still achieve proper headspacing. A measurement of belts on various cases and of the belt portion of various reamers quickly demonstrates that the variation in measurements is so great that consistent headspacing could not be achieved by relying on the belt. The belts on these cases were so that the cartridges could be fired in the newly popular bolt action guns without a rim to complicate feeding, and yet still allow use in the double rifles that were popular at the time and which use shotgun-type extractors designed to work on a rim. The belt replaced the rim in function on these new rimless cartridges.
It was introduced by the British company Holland & Holland in 1912 as the .375 Belted Rimless Nitro-Express. It initially used cordite
propellant which was made in long strands – hence the tapered shape of this cartridge, which was also to ensure smooth chambering and extraction from a rifle's breech
.
The .375 H&H is often cited as one of the most useful all-round rifle cartridges, especially where large and dangerous game occurs. With relatively light bullets in the region of 235 to 270 grains
(15 to 17 g), it is a flat-shooting, fairly long-range cartridge ideal for use on light to medium game. With heavy bullets of 300 grain (19 g) and greater, it has the punch necessary for large, thick-skinned dangerous game. In many regions with thick-skinned dangerous game animals, the .375 H&H is seen as the sensible minimum acceptable caliber, and in many places (in Africa, primarily) it is now the legal minimum for hunting such game. African game guides, professional hunters, and dangerous game cullers have repeatedly voted the .375 H&H as their clear preference for an all-round caliber, if they could only have one rifle. A similar preference has been expressed by Alaska game guides for brown and polar bear country
Unlike what is seen in most calibers, many .375 H&H rifles also achieve nearly the same point of impact over a wide range of bullet weights at all commonly used distances, further simplifying a professional hunter's choice in selecting different grain bullets based upon the game hunted, without requiring significant scope or sight adjustments, which further serves to popularize the .375 H&H Magnum among professional hunters (PHs).
The introduction of the 9.3x62mm Mauser cartridge in 1905 had a profound and lasting influence on hunters in Africa. Compared to the British double rifles, the Mauser was a far cheaper rifle to manufacture and therefore cheaper to acquire. Furthermore, while the double rifles gained little from industrialization the Mauser rifles had gained by for mass production, and were contracted to produce military rifles for many countries both inside and outside Europe. The result was cheap magazine rifles capable of firing one of the very best candidates for the all round hunting cartridge in Africa. The influence of Mauser's K98 action must not be understated; British gunmakers such as Rigby were purchasing the Mauser success K98 actions for use with their own cartridges. The popularity of the 9.3x62mm Mauser was so such that everyone from the German farmers in Africa to the White Hunters from Europe discarded their previous doubles and less powerful magazine rifles and took to the 9.3x62mm. The 9.3x62mm demonstrated that it was adequate for everything from the Elephant to the dik-dik and had acquired a reputation to match.
This trend did not go unnoticed by British rifle manufacturers. Between 1909 and 1911 Holland & Holland, Jeffrey, Rigby and Westley Richards introduced their own competing designs: .375 H&H Magnum, .404 Jeffery
, .416 Rigby
and the .425 Westley Richards
in an effort to stem the tide of the 9.3x62mm. Furthermore, the influence of the high-velocity craze begun by the Canadian .280 Ross
rifle had a marked effect on the Holland & Holland’s final design which also drew from their experience with the .400/.375 H&H cartridge.
Holland & Holland decided that the rifle had to fire a bullet with an adequate sectional density as the 286 gr bullet of the 9.3x62 mm Mauser cartridge which had demonstrated that it had the required penetration on thick skinned dangerous game. Secondly, the cartridge would require a high velocity so as to provide this penetration at extended ranges. The high velocity of the cartridge would have the added advantage of serving as a marketing tool. Thirdly, the cartridge must function reliably through a magazine rifle in tropical conditions and this required a tapered case working at lower pressures. Holland & Holland had determined that to provide adequate penetration a bullet with the sectional density similar to the 9.3x62mm required impact velocities of about 2150 ft/s (655.3 m/s). Drawing from anecdotal evidence of hunters it was also determined that high velocities provided impressive kills on game. Another added advantage of the high velocities what that a misjudgment with respect to range would be mitigated by the higher velocity.
Holland & Holland’s new cartridge was released together with a flanged version (.375 Flanged Magnum also known as the .375 Nitro Express) and was named the .375 Belted Rimless Nitro Express. It featured the belt from the .400/375 H&H cartridge, fired a 300 gr bullet which had the same sectional density of the 286 gr 9.3x62mm bullet at a velocity of 2500 ft/s (762 m/s). The cartridge burnt cordite and had a rather low working pressure of 47000 psi (3,240.5 bar) by modern standards so that spent cases would extract reliably in tropical environments of India and Africa.
The new cartridge was a proprietary design unlike the 9.3x62mm and was considerably longer than its German counterpart. While many .375 H&H rifles were built on the longer Mauser actions, these actions required modifications to allow for the feeding and cycling of the .375 H&H Magnum cartridge. So while the .375 H&H provided considerable advantages over the 9.3x62mm the significantly greater cost of the H&H rifles presented a roadblock to the adoption of the .375 H&H over the 9.3x62mm cartridge and remained for a time a less attractive option.
At the end of World War I Holland & Holland released the cartridge to the public for general trade. Also, new markets opened in America as more hunters sought to hunt in Africa. The .375 H&H was seen by many as the best medium bore cartridge available and which could be easily put to use hunting dangerous game in North America. Winchester was the first US gun maker to produce rifles chambered for the cartridge and did so beginning in 1925.
The end of World War II saw many gun makers turning to the civilian shooting market when war time contracts began running out. FN, Mauser, Remington and Winchester began turning out quality bolt action rifles and with increasing number of sportsmen taking to Africa saw the .375 H&H increasing in popularity. A further boost in popularity came when African colonies enacting legislation stipulating that the 9.3 mm (0.366141732283465 in) or the 0.375 in (9.5 mm) be the minimum bullet diameter for dangerous game. The legislating away of sub minimum cartridges forced the users of these cartridges to pick up a cartridge which qualified for the shooting of these game species and the logical choice was to move up to the .375 H&H Magnum.
The .375 H&H still remains a popular choice for the hunting of dangerous game. For the one gun hunter in Africa the .375 H&H is a very hard choice to beat as it provides a flat trajectory combined required for plains game with the hard hitting power required for dangerous game hunting.
Unlike previous cartridges, the .375 H&H operates at relatively higher pressures and was designed from the outset for use with smokeless powders that can generate higher pressures and thus higher velocities. However, when the cartridge was designed pressure levels were held to 47000 psi (3,240.5 bar) as cordite was sensitive to temperature and could cause dangerously high pressures in the hot tropical climates of Africa and India. However, modern smokeless powders are not as sensitive to ambient temperatures as cordite and therefore both the CIP and SAAMI provide far higher allowable pressures than the original loading of the cartridge allowed.
CIP recommends that commencement of rifling begin at 8.91 mm (0.350787401574803 in). Bore diameter is given as 9.3 mm (0.366141732283465 in) and groove diameter is 9.55 mm (0.375984251968504 in). CIP recommends a six grove barrel contour with each grove having an arc length of 2.92 mm (0.11496062992126 in) and a twist rate of one rotation in 305 mm (12 in). Maximum chamber pressure is given at 4300 bar (62,366.2 psi). There are no discrepancies between SAAMI and CIP values. However, CIP measures angle α (shoulder angle) as 29°55'43". SAAMI measure the shoulder angle as α/2 which is given by SAAMI to be 15°.
Today, a typical factory load such as Remington’s R375M1 or Federal’s ammunition will launch a 270 gr spitzer bullet at 2690 feet per second (819.9 m/s) with 4337 ft·lbf (5,880.2 J) of energy at the muzzle. This load has approximately the same trajectory as the 180-grain (12 g) bullet from a .30-06 Springfield. However while the .30-06 generates only about 2914 ft·lbf (3,950.9 J) compared with the .375 H&H. The 270 gr spitzer bullet at .375 H&H velocities has an maximum point black range (MPBR) of about 260 yd (237.7 m) when sighted in at about 220 yd (201.2 m).
The typical 300 gr ammunition manufactured by Federal and Remington have a muzzle velocity of 2530 feet per second (771.1 m/s) churning out 4263 ft·lbf (5,779.9 J) of energy. The 300 gr ammunition has a bullet trajectory similar to that of the .308 Winchester
firing a 180 gr bullet. The trajectory allows for an MPBR of about 245 yd (224 m) when zeroed in for 210 yd (192 m).
Scant attention is paid today to bullets in the 225 gr weight range as the .375 H&H has earned its reputation with the 300 gr bullets. At present no mainstream ammunition manufacturer produces ammunition loaded with these bullets. However these bullets are available for those wishing to handload. Bullets in this weight range can be launched at velocities of 2800–2900 ft/s (853.4–883.9 m/s).
Hornady new Superformance line of cartridges provides a leap in performance to the .375 H&H cartridge. The Superformance line uses a powders specifically blended for each cartridge. Hornady’s 375 H&H 270 gr SP-RP Superformance ammunition fires a 270 gr bullet at 2800 ft/s (853.4 m/s) for while the 375 H&H 300 gr DGS Superformance fires a 300 gr bullet at 2670 ft/s (813.8 m/s) generating 4699 ft·lbf (6,371 J) and 4748 ft·lbf (6,437.4 J) of energy respectively. The velocity and energy advantages this line of ammunition should invograte the .375 H&H cartridge.
The 9.3x64mm Brenneke cartridge is probably the closest European continental ballistic twin of the .375 Holland & Holland Magnum. When compared to the .375 Holland & Holland Magnum the 9.3x64mm Brenneke uses a bullet of a slightly smaller diameter of 0.366 in (9.3 mm) versus the .375 H&H which uses a 0.375 in (0.9525 cm) bullet a difference of only 0.009 in (0.2286 mm).
The .375 H&H Magnum was designed from the ground up as a dangerous game hunting cartridge and to take advantage of the smokeless propellants available at the turn of the 20th Century. As a cartridge design which was optimized for that sole purpose, it has found little to no use outside this sphere of usage. This is partly due to bullet selection as spitzer and round nose bullets are the norm, although Hornady does manufacture a 300 gr BTSP bullet with a high ballistic coefficient of .460 (G1).
Ammunition loaded with the 300 gr or heavier bullet the .375 H&H is adequate for heavy thick skinned dangerous game such as elephant and rhinoceros in most conditions. Today, due to pace at which hunting is conducted and the requirement of success within certain time constrains, the .375 H&H Magnum is considered under powered for elephant, rhinoceros and buffalo as the only shooting situation that might present itself might be an adverse one. However, there is little doubt that it has been successfully been used to take these heavy dangerous game species. There is some speculation that the .375 H&H Magnum has been used to take more Big Five game than any other cartridge. Even today, many professional hunters, outfitters and wildlife management personnel in Africa continue to rely on the .375 H&H Magnum to carry out their duties throughout the continent.
The .375 H&H is probably the best choice for recoil sensitive hunters pursuing heavy dangerous game species due to its comparatively low recoil in comparison to big bore cartridges such as .416 Rigby or the .458 Winchester Magnum. Furthermore, rifles which chamber the cartridge are frequently lighter and handier than those mode for its larger counterparts. Since the cartridge is adequate for even elephant and African cape buffalo under most shooting circumstances that would be encountered, this cartridge is an excellent compromise between killing power, handiness and shootability making it one of the best balanced cartridges available.
Equipped with 300 gr bullets, the .375 H&H an excellent choice for heavy game species such as the giant eland, giraffe, Asiatic water buffalo. The .375 H&H using the 300 gr expanding bullets makes an excellent choice for large bears such as the Alaskan brown bear and the polar bear, large ungulates such as the North American bison, Asiatic water buffalo and the giraffe. Many North American guides in Alaska and Northern Canada carry the .375 H&H to back up their clients should an encounter with one of the large bear species is likely.
Bullets weighing 325 gr will have sectional densities between .330 and .356. These bullets can be launched at velocities between 2380–2470 ft/s (725.4–752.9 m/s) giving these bullets greater penetration than a 500 gr .458 bullet at 2240 ft/s (682.8 m/s).
Bullets weighting in the range of 250 gr perfect for the largest cats such as the lion or tiger. While these felids do not require extremely powerful cartridges, (a .300 Winchester Magnum can considered a minimum for these cats), local requirements or regulations may require a larger cartridge than the .375 H&H Magnum. This range of bullets also is a great choice for most plains game species in Africa, elk, red deer and moose (called elk in Europe) in North America and Europe.
There are a great number of rifles (and even a few handguns) chambered for the .375 H&H. Many types of actions are used, including single-shots, double-rifles, and bolt actions. When hunting dangerous game, a double-rifle or a controlled-feed bolt action rifle is most commonly recommended, as a quick follow-up shot may be necessary, and reliability of the firearm becomes of paramount importance.
The one sport in which the .375 H&H Magnum has made some gains in has been the Big Bore Shoots such as those sponsored by the Big Bore Association of South Africa and its affiliated chapters. The .375 H&H Magnum is considered a transitional bore by the association and the minimum cartridge which is allowable for score keeping.
The CIP has published mandatory specifications for the .375 Flanged Magnum. Bore ∅ for the cartridge is 9.3 mm (0.366141732283465 in) and the groove ∅ is 9.55 mm (0.375984251968504 in). The barrel will have 6 grooves with a twist of one revolution in 305 mm (12 in) and each groove being 2.92 mm (0.11496062992126 in)wide. SAAMI has not published specifications nor recommendations in regard to this cartridge.
The cartridge is capable of firing a 235 gr bullet at 2800 ft/s (853.4 m/s), a 270 gr bullet at 2650 ft/s (807.7 m/s) and a 300 gr bullet at 2500 ft/s (762 m/s) with muzzle energies of 4090 ft·lbf (5,545.3 J),4200 ft·lbf (5,694.4 J) and 4160 ft·lbf (5,640.2 J) respectively. The cartridge is appropriate for all game species as the .375 H&H Magnum cartridge.
when they were introduced together in August, 1912. This second belted case design was later used with the .300 H&H Magnum
, and has been modified as the basis for "Magnum" cartridges developed by other arms manufacturers.
.30 Super
– Essentially a slightly modified .300 H&H case made by Winchester
.300 Weatherby Magnum
– via the full length .30 Super improved
7mm Shooting Times Westerner
– Via the 8mm Remington Magnum
8 mm Remington Magnum
– necked down improved .375 H&H case
.340 Weatherby Magnum
– via the full length .30 Super improved
.358 Shooting Times Alaskan – Via the 8mm Remington Magnum
.375 Weatherby Magnum
– via the .30 Super improved
.416 Remington Magnum
– via the 8mm Remington Magnum
.458 Lott
– based directly on the .375 H&H case
.470 Capstick
– based directly on the .375 H&H case
– via the .30 Super
.264 Winchester Magnum
– based directly on the .375 H&H case
.270 Weatherby Magnum
– via the .30 Super
7mm Remington Magnum – via the .264 Winchester Magnum case
7 mm Weatherby Magnum
– via the .30 Super
.300 Winchester Magnum
– based directly on the .375 H&H case
.308 Norma Magnum
– used standard length Weatherby cases
.338 Winchester Magnum – based directly on the .375 H&H case
.358 Norma Magnum
– used standard length Weatherby cases
.458 Winchester Magnum
– based directly on the .375 H&H case
.350 Remington Magnum
– via the 7mm Remington Magnum
Rifle
A rifle is a firearm designed to be fired from the shoulder, with a barrel that has a helical groove or pattern of grooves cut into the barrel walls. The raised areas of the rifling are called "lands," which make contact with the projectile , imparting spin around an axis corresponding to the...
round and one of the best-known and most popular medium-bore
Caliber
In guns including firearms, caliber or calibre is the approximate internal diameter of the barrel in relation to the diameter of the projectile used in it....
cartridges in the world. The .375 H&H was only the second cartridge ever to feature a belt, now common among magnum rounds. A popular misconception is that the belt is for headspace, with some saying it is due to the narrow shoulder. However, many cartridges with much smaller shoulders and greater taper have no belt at all and still achieve proper headspacing. A measurement of belts on various cases and of the belt portion of various reamers quickly demonstrates that the variation in measurements is so great that consistent headspacing could not be achieved by relying on the belt. The belts on these cases were so that the cartridges could be fired in the newly popular bolt action guns without a rim to complicate feeding, and yet still allow use in the double rifles that were popular at the time and which use shotgun-type extractors designed to work on a rim. The belt replaced the rim in function on these new rimless cartridges.
It was introduced by the British company Holland & Holland in 1912 as the .375 Belted Rimless Nitro-Express. It initially used cordite
Cordite
Cordite is a family of smokeless propellants developed and produced in the United Kingdom from 1889 to replace gunpowder as a military propellant. Like gunpowder, cordite is classified as a low explosive because of its slow burning rates and consequently low brisance...
propellant which was made in long strands – hence the tapered shape of this cartridge, which was also to ensure smooth chambering and extraction from a rifle's breech
Breech-loading weapon
A breech-loading weapon is a firearm in which the cartridge or shell is inserted or loaded into a chamber integral to the rear portion of a barrel....
.
The .375 H&H is often cited as one of the most useful all-round rifle cartridges, especially where large and dangerous game occurs. With relatively light bullets in the region of 235 to 270 grains
Grain (measure)
A grain is a unit of measurement of mass that is nominally based upon the mass of a single seed of a cereal. From the Bronze Age into the Renaissance the average masses of wheat and barley grains were part of the legal definition of units of mass. However, there is no evidence of any country ever...
(15 to 17 g), it is a flat-shooting, fairly long-range cartridge ideal for use on light to medium game. With heavy bullets of 300 grain (19 g) and greater, it has the punch necessary for large, thick-skinned dangerous game. In many regions with thick-skinned dangerous game animals, the .375 H&H is seen as the sensible minimum acceptable caliber, and in many places (in Africa, primarily) it is now the legal minimum for hunting such game. African game guides, professional hunters, and dangerous game cullers have repeatedly voted the .375 H&H as their clear preference for an all-round caliber, if they could only have one rifle. A similar preference has been expressed by Alaska game guides for brown and polar bear country
Unlike what is seen in most calibers, many .375 H&H rifles also achieve nearly the same point of impact over a wide range of bullet weights at all commonly used distances, further simplifying a professional hunter's choice in selecting different grain bullets based upon the game hunted, without requiring significant scope or sight adjustments, which further serves to popularize the .375 H&H Magnum among professional hunters (PHs).
History & Origins
.375 H&H Magnum is the result of competition between British rifle manufacturers to develop new cartridges to take advantage of the new smokeless powders. The 9.5x57mm Mannlicher-Schönauer cartridge had a major influence on British rifle manufacturers and was soon adopted by Westley Richards and Eley as the .375 Rimless Nitro Express 2.25”. In an effort to compete, Holland & Holland introduced the .400/375 Belted Nitro Express. The .400/375 H&H (also known as the .375 Velopex) as it is sometimes known was the first cartridge manufactured to feature a belt. The addition of a belt to a rimless cartridge design provided the advantage of allowing for correct headspacing of highly tapered cartridges (an advantage of flanged cartridges) and smooth feeding through magazine rifles (the advantage of rimless cartridges).The introduction of the 9.3x62mm Mauser cartridge in 1905 had a profound and lasting influence on hunters in Africa. Compared to the British double rifles, the Mauser was a far cheaper rifle to manufacture and therefore cheaper to acquire. Furthermore, while the double rifles gained little from industrialization the Mauser rifles had gained by for mass production, and were contracted to produce military rifles for many countries both inside and outside Europe. The result was cheap magazine rifles capable of firing one of the very best candidates for the all round hunting cartridge in Africa. The influence of Mauser's K98 action must not be understated; British gunmakers such as Rigby were purchasing the Mauser success K98 actions for use with their own cartridges. The popularity of the 9.3x62mm Mauser was so such that everyone from the German farmers in Africa to the White Hunters from Europe discarded their previous doubles and less powerful magazine rifles and took to the 9.3x62mm. The 9.3x62mm demonstrated that it was adequate for everything from the Elephant to the dik-dik and had acquired a reputation to match.
This trend did not go unnoticed by British rifle manufacturers. Between 1909 and 1911 Holland & Holland, Jeffrey, Rigby and Westley Richards introduced their own competing designs: .375 H&H Magnum, .404 Jeffery
.404 Jeffery
The .404 Jeffery is a large caliber, rimless cartridge designed for large, dangerous game, such as the big five of Africa. Other names for this cartridge include .404 Jeffery Rimless, .404 Rimless Nitro Express, and 10.75 × 73 mm...
, .416 Rigby
.416 Rigby
The .416 Rigby or 10.6x74mm was designed in 1911 by John Rigby & Company of London, England as a dangerous game cartridge and is the first one to use a bullet with a diameter of .416"...
and the .425 Westley Richards
.425 Westley Richards
The .425 Westley Richards Magnum is one of the classic African big-game rounds. It is a cartridge invented by Leslie Taylor of Westley Richards, a gunmaking firm of Birmingham England in 1909 as a proprietary cartridge for their bolt action rifles...
in an effort to stem the tide of the 9.3x62mm. Furthermore, the influence of the high-velocity craze begun by the Canadian .280 Ross
.280 Ross
The .280 Ross, also known as the .280 Nitro, .280 Rimless Nitro Express Ross and .280 Rimless cartridge, is an approximately 7mm bullet diameter rifle round developed in Canada by F.W...
rifle had a marked effect on the Holland & Holland’s final design which also drew from their experience with the .400/.375 H&H cartridge.
Holland & Holland decided that the rifle had to fire a bullet with an adequate sectional density as the 286 gr bullet of the 9.3x62 mm Mauser cartridge which had demonstrated that it had the required penetration on thick skinned dangerous game. Secondly, the cartridge would require a high velocity so as to provide this penetration at extended ranges. The high velocity of the cartridge would have the added advantage of serving as a marketing tool. Thirdly, the cartridge must function reliably through a magazine rifle in tropical conditions and this required a tapered case working at lower pressures. Holland & Holland had determined that to provide adequate penetration a bullet with the sectional density similar to the 9.3x62mm required impact velocities of about 2150 ft/s (655.3 m/s). Drawing from anecdotal evidence of hunters it was also determined that high velocities provided impressive kills on game. Another added advantage of the high velocities what that a misjudgment with respect to range would be mitigated by the higher velocity.
Holland & Holland’s new cartridge was released together with a flanged version (.375 Flanged Magnum also known as the .375 Nitro Express) and was named the .375 Belted Rimless Nitro Express. It featured the belt from the .400/375 H&H cartridge, fired a 300 gr bullet which had the same sectional density of the 286 gr 9.3x62mm bullet at a velocity of 2500 ft/s (762 m/s). The cartridge burnt cordite and had a rather low working pressure of 47000 psi (3,240.5 bar) by modern standards so that spent cases would extract reliably in tropical environments of India and Africa.
The new cartridge was a proprietary design unlike the 9.3x62mm and was considerably longer than its German counterpart. While many .375 H&H rifles were built on the longer Mauser actions, these actions required modifications to allow for the feeding and cycling of the .375 H&H Magnum cartridge. So while the .375 H&H provided considerable advantages over the 9.3x62mm the significantly greater cost of the H&H rifles presented a roadblock to the adoption of the .375 H&H over the 9.3x62mm cartridge and remained for a time a less attractive option.
At the end of World War I Holland & Holland released the cartridge to the public for general trade. Also, new markets opened in America as more hunters sought to hunt in Africa. The .375 H&H was seen by many as the best medium bore cartridge available and which could be easily put to use hunting dangerous game in North America. Winchester was the first US gun maker to produce rifles chambered for the cartridge and did so beginning in 1925.
The end of World War II saw many gun makers turning to the civilian shooting market when war time contracts began running out. FN, Mauser, Remington and Winchester began turning out quality bolt action rifles and with increasing number of sportsmen taking to Africa saw the .375 H&H increasing in popularity. A further boost in popularity came when African colonies enacting legislation stipulating that the 9.3 mm (0.366141732283465 in) or the 0.375 in (9.5 mm) be the minimum bullet diameter for dangerous game. The legislating away of sub minimum cartridges forced the users of these cartridges to pick up a cartridge which qualified for the shooting of these game species and the logical choice was to move up to the .375 H&H Magnum.
The .375 H&H still remains a popular choice for the hunting of dangerous game. For the one gun hunter in Africa the .375 H&H is a very hard choice to beat as it provides a flat trajectory combined required for plains game with the hard hitting power required for dangerous game hunting.
Design & Specifications
The .375 H&H Magnum case design was conceived to use cordite; a stick type propellant used widely in the United Kingdom. The tapering cartridge body design and the small shallow shoulder are typical aspects of cartridges optimized for the use of this propellant. An advantage of such a case design is that it will feed and extract smoothly thus contributing to the cartridge's reliability in the field.Unlike previous cartridges, the .375 H&H operates at relatively higher pressures and was designed from the outset for use with smokeless powders that can generate higher pressures and thus higher velocities. However, when the cartridge was designed pressure levels were held to 47000 psi (3,240.5 bar) as cordite was sensitive to temperature and could cause dangerously high pressures in the hot tropical climates of Africa and India. However, modern smokeless powders are not as sensitive to ambient temperatures as cordite and therefore both the CIP and SAAMI provide far higher allowable pressures than the original loading of the cartridge allowed.
CIP recommends that commencement of rifling begin at 8.91 mm (0.350787401574803 in). Bore diameter is given as 9.3 mm (0.366141732283465 in) and groove diameter is 9.55 mm (0.375984251968504 in). CIP recommends a six grove barrel contour with each grove having an arc length of 2.92 mm (0.11496062992126 in) and a twist rate of one rotation in 305 mm (12 in). Maximum chamber pressure is given at 4300 bar (62,366.2 psi). There are no discrepancies between SAAMI and CIP values. However, CIP measures angle α (shoulder angle) as 29°55'43". SAAMI measure the shoulder angle as α/2 which is given by SAAMI to be 15°.
Performance
When the .375 H&H Magnum was released in 1912 it was loaded with three bullet weights: a 235 gr at 2800 ft/s (853.4 m/s), 270 gr at 2650 ft/s (807.7 m/s)and a 300 gr at 2500 ft/s (762 m/s). However, today, with the availability of a wide range of powders, velocities gains of 150–200 ft/s (45.7–61 m/s) can be realized. Acceptable bullet weights for the .375 H&H Magnum range from 200 gr to 380 gr. The lighter bullets, those weighting 210 gr to 235 gr are suitable for lighter plains game. Bullets weighting between 250 gr to 285 gr can be used on heavy bodied plains game. Bullets weighting 285 gr to 300 gr should be reserved for heavy dangerous game.Today, a typical factory load such as Remington’s R375M1 or Federal’s ammunition will launch a 270 gr spitzer bullet at 2690 feet per second (819.9 m/s) with 4337 ft·lbf (5,880.2 J) of energy at the muzzle. This load has approximately the same trajectory as the 180-grain (12 g) bullet from a .30-06 Springfield. However while the .30-06 generates only about 2914 ft·lbf (3,950.9 J) compared with the .375 H&H. The 270 gr spitzer bullet at .375 H&H velocities has an maximum point black range (MPBR) of about 260 yd (237.7 m) when sighted in at about 220 yd (201.2 m).
The typical 300 gr ammunition manufactured by Federal and Remington have a muzzle velocity of 2530 feet per second (771.1 m/s) churning out 4263 ft·lbf (5,779.9 J) of energy. The 300 gr ammunition has a bullet trajectory similar to that of the .308 Winchester
.308 Winchester
The .308 Winchester is a rifle cartridge and is the commercial cartridge upon which the military 7.62x51mm NATO centerfire cartridge is based. The .308 Winchester was introduced in 1952, two years prior to the NATO adoption of the 7.62x51mm NATO T65...
firing a 180 gr bullet. The trajectory allows for an MPBR of about 245 yd (224 m) when zeroed in for 210 yd (192 m).
Scant attention is paid today to bullets in the 225 gr weight range as the .375 H&H has earned its reputation with the 300 gr bullets. At present no mainstream ammunition manufacturer produces ammunition loaded with these bullets. However these bullets are available for those wishing to handload. Bullets in this weight range can be launched at velocities of 2800–2900 ft/s (853.4–883.9 m/s).
Hornady new Superformance line of cartridges provides a leap in performance to the .375 H&H cartridge. The Superformance line uses a powders specifically blended for each cartridge. Hornady’s 375 H&H 270 gr SP-RP Superformance ammunition fires a 270 gr bullet at 2800 ft/s (853.4 m/s) for while the 375 H&H 300 gr DGS Superformance fires a 300 gr bullet at 2670 ft/s (813.8 m/s) generating 4699 ft·lbf (6,371 J) and 4748 ft·lbf (6,437.4 J) of energy respectively. The velocity and energy advantages this line of ammunition should invograte the .375 H&H cartridge.
The 9.3x64mm Brenneke cartridge is probably the closest European continental ballistic twin of the .375 Holland & Holland Magnum. When compared to the .375 Holland & Holland Magnum the 9.3x64mm Brenneke uses a bullet of a slightly smaller diameter of 0.366 in (9.3 mm) versus the .375 H&H which uses a 0.375 in (0.9525 cm) bullet a difference of only 0.009 in (0.2286 mm).
Sporting Usage
The .375 H&H Magnum is one of the most versatile cartridges and is referred to by Jack O’Connor as the "Queen of the Medium Bores". The cartridge is very popular in Africa where it is considered one of the best all-round rifle cartridges. It is capable of taking any big species including all the Big Five game animals. The big game hunter, John ”Pondoro” Taylor, held the .375 H&H Magnum in such high esteem that he dedicated a chapter in the book African Rifles and Cartridges.The .375 H&H Magnum was designed from the ground up as a dangerous game hunting cartridge and to take advantage of the smokeless propellants available at the turn of the 20th Century. As a cartridge design which was optimized for that sole purpose, it has found little to no use outside this sphere of usage. This is partly due to bullet selection as spitzer and round nose bullets are the norm, although Hornady does manufacture a 300 gr BTSP bullet with a high ballistic coefficient of .460 (G1).
Ammunition loaded with the 300 gr or heavier bullet the .375 H&H is adequate for heavy thick skinned dangerous game such as elephant and rhinoceros in most conditions. Today, due to pace at which hunting is conducted and the requirement of success within certain time constrains, the .375 H&H Magnum is considered under powered for elephant, rhinoceros and buffalo as the only shooting situation that might present itself might be an adverse one. However, there is little doubt that it has been successfully been used to take these heavy dangerous game species. There is some speculation that the .375 H&H Magnum has been used to take more Big Five game than any other cartridge. Even today, many professional hunters, outfitters and wildlife management personnel in Africa continue to rely on the .375 H&H Magnum to carry out their duties throughout the continent.
The .375 H&H is probably the best choice for recoil sensitive hunters pursuing heavy dangerous game species due to its comparatively low recoil in comparison to big bore cartridges such as .416 Rigby or the .458 Winchester Magnum. Furthermore, rifles which chamber the cartridge are frequently lighter and handier than those mode for its larger counterparts. Since the cartridge is adequate for even elephant and African cape buffalo under most shooting circumstances that would be encountered, this cartridge is an excellent compromise between killing power, handiness and shootability making it one of the best balanced cartridges available.
Equipped with 300 gr bullets, the .375 H&H an excellent choice for heavy game species such as the giant eland, giraffe, Asiatic water buffalo. The .375 H&H using the 300 gr expanding bullets makes an excellent choice for large bears such as the Alaskan brown bear and the polar bear, large ungulates such as the North American bison, Asiatic water buffalo and the giraffe. Many North American guides in Alaska and Northern Canada carry the .375 H&H to back up their clients should an encounter with one of the large bear species is likely.
Bullets weighing 325 gr will have sectional densities between .330 and .356. These bullets can be launched at velocities between 2380–2470 ft/s (725.4–752.9 m/s) giving these bullets greater penetration than a 500 gr .458 bullet at 2240 ft/s (682.8 m/s).
Bullets weighting in the range of 250 gr perfect for the largest cats such as the lion or tiger. While these felids do not require extremely powerful cartridges, (a .300 Winchester Magnum can considered a minimum for these cats), local requirements or regulations may require a larger cartridge than the .375 H&H Magnum. This range of bullets also is a great choice for most plains game species in Africa, elk, red deer and moose (called elk in Europe) in North America and Europe.
There are a great number of rifles (and even a few handguns) chambered for the .375 H&H. Many types of actions are used, including single-shots, double-rifles, and bolt actions. When hunting dangerous game, a double-rifle or a controlled-feed bolt action rifle is most commonly recommended, as a quick follow-up shot may be necessary, and reliability of the firearm becomes of paramount importance.
The one sport in which the .375 H&H Magnum has made some gains in has been the Big Bore Shoots such as those sponsored by the Big Bore Association of South Africa and its affiliated chapters. The .375 H&H Magnum is considered a transitional bore by the association and the minimum cartridge which is allowable for score keeping.
Variants
The .375 H&H Magnum long tapering body and shallow shoulders are generally believed not to promote long case life due to case head separation above the belt. The case design does not promote the optimal use of the cartridge size to gain performance. Modern cartridges have very little taper so as to benefit from a larger powder capacity. It comes as no surprise that there have been a few attempts to improve the performance of the cartridge..375 Flanged Magnum
The .375 Flanged Magnum also known as the .375 H&H Flanged Magnum and the .375 Flanged Nitro Express is the companion cartridge to the .375 H&H Magnum for use in double and single shot rifles and was released together with the .375 H&H Magnum by Holland & Holland. It is considered the flanged (rimmed) version of the .375 H&H Magnum. The flanged cartridge is loaded to a lower pressure of 3250 bar (47,137.3 psi) in comparison to the .375H&H Magnum.The CIP has published mandatory specifications for the .375 Flanged Magnum. Bore ∅ for the cartridge is 9.3 mm (0.366141732283465 in) and the groove ∅ is 9.55 mm (0.375984251968504 in). The barrel will have 6 grooves with a twist of one revolution in 305 mm (12 in) and each groove being 2.92 mm (0.11496062992126 in)wide. SAAMI has not published specifications nor recommendations in regard to this cartridge.
The cartridge is capable of firing a 235 gr bullet at 2800 ft/s (853.4 m/s), a 270 gr bullet at 2650 ft/s (807.7 m/s) and a 300 gr bullet at 2500 ft/s (762 m/s) with muzzle energies of 4090 ft·lbf (5,545.3 J),4200 ft·lbf (5,694.4 J) and 4160 ft·lbf (5,640.2 J) respectively. The cartridge is appropriate for all game species as the .375 H&H Magnum cartridge.
.375 H&H Ackley Improved
The .375 H&H Ackley Improved was a cartridge designed by P.O. Ackley in an effort improve on the performance and case life of the .375 H&H Magnum. The improved case follows the formulaic Ackley design of a body of little taper and steep shoulder of 40°. The cartridge was found to be capable of 2830 ft/s (862.6 m/s) with a 270 gr bullet. A .375 H&H Magnum cartridge can be chambered and fired safely in a Ackley Improved chamber but with a loss of performance. .375 H&H Magnum case thus fired will form to the Ackley Improved chamber..375 Weatherby Magnum
The .375 Weatherby Magnum is in reality an improved case like the .375 H&H Ackley Improved. The case was designed by Roy Weatherby in 1944 and features the Weatherby double radius shoulder typical of all Weatherby cartridges. The .375 Weatherby Magnum is capable of launching a 300 gr at 2800 ft/s (853.4 m/s). The .375 H&H Magnum can be fired in the chamber of a .375 Weatherby Magnum with a slight loss in performance. Unlike the .375 H&H AI cartridge, the .375 Weatherby Magnum is loaded to higher pressures than the parent cartridge.As a Parent Cartridge
The distinctive belted case of this cartridge was patented in Britain on 31 March 1891 by G. Roth of Austria. The first commercial use of the patent was in 1907 for the .375 Holland-Schoenauer cartridge for a Mannlicher-Schoenauer bolt-action rifle marketed by Holland & Holland. The .375 H&H used an improved belted case shared with the .275 H&H Magnum.275 H&H Magnum
The .275 Holland & Holland Magnum is a semi-obsolete rifle cartridge similar to the 7mm Remington Magnum. It was introduced by the British company Holland & Holland in 1912 with a shorter version of the belted case of the .375 H&H Magnum introduced the same year as the .375 Belted Rimless...
when they were introduced together in August, 1912. This second belted case design was later used with the .300 H&H Magnum
.300 H&H Magnum
The .300 H&H Magnum Cartridge was introduced by the British company Holland & Holland as the Super-Thirty in June, 1925. The case was belted like the .375 H&H Magnum, and is based on the same case, as also is the .244 H&H Magnum. The belt is for headspace as the cases' shoulders have a narrow...
, and has been modified as the basis for "Magnum" cartridges developed by other arms manufacturers.
Cartridges based on the full length .375 H&H Magnum case
.300 H&H Magnum – based directly on the .375 H&H case. Adopted in the US as the .30 Super..30 Super
.300 H&H Magnum
The .300 H&H Magnum Cartridge was introduced by the British company Holland & Holland as the Super-Thirty in June, 1925. The case was belted like the .375 H&H Magnum, and is based on the same case, as also is the .244 H&H Magnum. The belt is for headspace as the cases' shoulders have a narrow...
– Essentially a slightly modified .300 H&H case made by Winchester
.300 Weatherby Magnum
.300 Weatherby Magnum
The .300 Weatherby Magnum is a .30 caliber rifle cartridge created by Roy Weatherby in 1944 and produced by Weatherby. It has become the most popular of all the Weatherby cartridges.-Background:...
– via the full length .30 Super improved
7mm Shooting Times Westerner
7 mm STW
The 7mm Shooting Times Westerner, sometimes refereed to as the 7mm STW began as a wildcat rifle cartridge developed by Layne Simpson in 1979. It is an 8 mm Remington Magnum case that has been "necked down" by 1 mm to accept 7 mm bullets...
– Via the 8mm Remington Magnum
8 mm Remington Magnum
8 mm Remington Magnum
The 8mm Remington Magnum belted rifle cartridge was introduced by Remington Arms Company in 1978 as a new chambering for the model 700 BDL rifle. The 8 mm Remington Magnum's parent case is the .375 H&H Magnum...
– necked down improved .375 H&H case
.340 Weatherby Magnum
.340 Weatherby Magnum
The .340 Weatherby Magnum rifle cartridge was introduced in 1963 by creator Roy Weatherby in response to the .338 Winchester Magnum. The .340 Weatherby Magnum uses the same .338 in. diameter bullets as the .338 Winchester Magnum but it does so at greater velocity than its Winchester competition...
– via the full length .30 Super improved
.358 Shooting Times Alaskan – Via the 8mm Remington Magnum
.375 Weatherby Magnum
.375 Weatherby Magnum
The .375 Weatherby Magnum is a .37 caliber rifle cartridge. The cartridge is a blown out, improved and provided with the Weatherby double radius shoulder – given the Weatherby treatment – version of the .375 H&H Magnum...
– via the .30 Super improved
.416 Remington Magnum
.416 Remington Magnum
The .416 Remington Magnum is a .416 caliber of a belted bottle-necked design. The cartridge was intended as a dangerous game hunting cartridge and released to the public in 1989. The cartridge uses the case of the 8 mm Remington Magnum as a parent cartridge. When the cartridge was released in...
– via the 8mm Remington Magnum
.458 Lott
.458 Lott
The .458 Lott is a .458 caliber belted hunting cartridge designed as a replacement for the less powerful .458 Winchester Magnum. It is based on the full length .375 H&H Magnum blown out and shortened to...
– based directly on the .375 H&H case
.470 Capstick
.470 Capstick
The .470 Capstick is a rifle cartridge created by Col. Arthur B Alphin from A-Square in 1990, named after writer and hunter Peter Hathaway Capstick. It is based on a .375 H&H Magnum case blown out and necked to accept a .475 inch bullet...
– based directly on the .375 H&H case
Standard length cartridges based on the .375 H&H Magnum case
.257 Weatherby Magnum.257 Weatherby Magnum
The .257 Weatherby Magnum is a .25 Caliber belted bottlenecked cartridge. It is one of the original standard length magnums developed by shortening the .375 H&H Magnum case to approx....
– via the .30 Super
.264 Winchester Magnum
.264 Winchester Magnum
The .264 Winchester Magnum is a belted, bottlenecked rifle cartridge. Apart from the .257 Weatherby Magnum, it is the smallest caliber factory cartridge which uses the standard length Holland & Holland belted magnum case...
– based directly on the .375 H&H case
.270 Weatherby Magnum
.270 Weatherby Magnum
The .270 Weatherby Magnum was the first belted magnum based on the .300 H&H Magnum to be developed by Roy Weatherby. It has the characteristic double-radius shoulders and is necked down to accommodate the .277in bullets. Being a proprietary cartridge, the .270 Weatherby has no official SAAMI...
– via the .30 Super
7mm Remington Magnum – via the .264 Winchester Magnum case
7 mm Weatherby Magnum
7 mm Weatherby Magnum
The 7 mm Weatherby Magnum is a powerful 7 mm rifle cartridge offered by the Weatherby firearms company in their Mark V rifles. The cartridge was one of the first cartridges offered by the Weatherby company....
– via the .30 Super
.300 Winchester Magnum
.300 Winchester Magnum
The .300 Winchester Magnum is a popular, belted, bottlenecked magnum rifle cartridge that was introduced by Winchester Repeating Arms Company in 1963 as a member of the family of Winchester Magnum cartridges. The .300 Winchester Magnum is a magnum cartridge designed to fit in a standard length...
– based directly on the .375 H&H case
.308 Norma Magnum
.308 Norma Magnum
The .308 Norma Magnum cartridge was created by Nils Kvale at Norma, Sweden. Like the larger .358 Norma Magnum it is based on the .300 H&H Magnum. The length of the case is the longest that would fit in a standard Mauser action. While it appeared to have a bright future initially, it was soon...
– used standard length Weatherby cases
.338 Winchester Magnum – based directly on the .375 H&H case
.358 Norma Magnum
.358 Norma Magnum
The .358 Norma Magnum is a bolt action rifle cartridge introduced in 1959 by Swedish company, Norma. It is closely related to the smaller .308 Norma Magnum. Both calibers share the same dimensions of the case head as the .300 H&H Magnum. The length of the case is the longest possible that would...
– used standard length Weatherby cases
.458 Winchester Magnum
.458 Winchester Magnum
The .458 Winchester Magnum is a belted, straight-taper cased, dangerous game rifle cartridge. It was introduced commercially in 1956 by Winchester and first chambered in the Winchester Model 70 African rifle. It was designed to compete against the .450 Nitro Express and the .470 Nitro Express...
– based directly on the .375 H&H case
Short action cartridges based on the .375 H&H Magnum case
6.5mm Remington Magnum – via the .350 Remington Magnum.350 Remington Magnum
.350 Remington Magnum
The .350 Remington Magnum was introduced in 1965 by Remington Arms Company for the Model 600 rifle. It was later offered in the Model 660 and Model 700 rifles but was discontinued as a regular factory chambering in 1974 after a poor sales record...
– via the 7mm Remington Magnum
See also
- List of rifle cartridges
- Table of pistol and rifle cartridges by yearTable of pistol and rifle cartridges by yearTable of selected handgun, submachine gun, rifle and machine gun cartridges by year....
- 9 mm caliber9 mm caliberThis article lists firearm cartridges which have a bullet in the caliber range. The most prevalent of these rounds is the 9x19mm Parabellum.*Length refers to the cartridge case length.*OAL refers to the overall length of the cartridge....