Understanding Calibre Families
New to Double Rifles — 05
Understanding Calibre Families
The calibres available for double rifles span an enormous range — from cartridges suited to plains game and medium dangerous game all the way to the great elephant cartridges of the Victorian era. Understanding how they group into families, what each family was designed to do, and where the boundaries between them lie is the foundation of choosing the right rifle for the hunting you intend to do.
Walk into any serious gunroom and you will find double rifles chambered for cartridges whose names mean nothing to someone new to the field. The .470 Nitro Express. The .450/400. The 9.3x74R. The .375 H&H. The .500 Nitro Express. These are not arbitrary designations — each sits within a family of cartridges that share a design philosophy, a performance envelope, and a history. Once you understand the families, the individual cartridges start to make sense.
The simplest way to organise double rifle calibres is by the job they were designed to do. Three broad groups cover almost everything you will encounter: medium-bore cartridges for plains game and lighter dangerous game; the classic dangerous-game Nitro Express cartridges for buffalo, lion, leopard, and elephant at close range; and the large-bore stopping cartridges for the heaviest and most dangerous work at very close quarters. There is overlap between the groups, and experienced hunters disagree about where the lines fall — but the framework is useful.
The medium bores: .375 to .416
The medium bores are the most versatile cartridges in the double rifle world. They are powerful enough for dangerous game in the right hands and at appropriate distances, yet manageable enough for a full day's hunting without the cumulative punishment of the larger Nitro Express rounds. For a hunter who wants one rifle that can cover plains game, leopard, lion, and buffalo — and who is not pursuing elephant as a primary quarry — a medium bore is a rational and well-supported choice.
9.3x74R
The 9.3x74R is the Continental European answer to the medium-bore question, and it is the cartridge I know best from my own combination gun. The rimmed case was designed specifically for break-open actions — the "R" in the name stands for "Rand," the German term for rim. It pushes a 286-grain bullet at around 2,360 fps, producing energy figures that sit comfortably in the dangerous-game range. It is widely used across Africa and Europe, ammunition is relatively easy to source, and the recoil in a well-fitted rifle is entirely manageable. For a first double rifle that will see mixed use, the 9.3x74R deserves serious consideration.
.375 H&H Magnum
The .375 H&H is technically a bolt-action cartridge — it uses a belted rimless case — but it appears in double rifles often enough to warrant mention here. Holland & Holland introduced it in 1912, and it became one of the most widely distributed dangerous-game cartridges in the world. Many African countries set the .375 H&H as the legal minimum for dangerous game. In a double rifle it is an unusual choice, since the belted case does not headspace as cleanly in a break-open action as a rimmed cartridge, but it has been done and done well. More commonly, hunters who want .375-class performance in a double reach for the .375 Flanged Nitro Express — a rimmed version of essentially the same concept.
.416 Rigby and .416 Remington
The .416 bore sits between the medium bores and the classic Nitro Express cartridges. John Rigby introduced the .416 Rigby in 1911 as a bolt-action cartridge, but it has been chambered in double rifles. It drives a 400-grain bullet at around 2,370 fps — more energy than the 9.3x74R, less recoil than the .470 NE. For hunters who find the classic Nitro Express cartridges more rifle than they need but want something heavier than the 9.3, the .416 family occupies a useful middle ground.
The medium bores are not a compromise. For most dangerous-game hunting — buffalo, lion, leopard — a well-placed shot from a 9.3x74R or .375 Flanged is entirely sufficient. The larger Nitro Express cartridges exist for specific situations, not as a general upgrade.
The classic Nitro Express cartridges: .450 to .500
This is the heart of the double rifle world. The cartridges in this group — the .470 NE, the .500 NE, the .450 NE, the .450/400 NE, the .404 Jeffery — were designed specifically for dangerous game at close range in thick cover. They share a common philosophy: heavy bullets at moderate velocity, relying on mass and sectional density for penetration rather than speed. They are rimmed cases, designed for break-open actions, and they have been in continuous or near-continuous production for over a century.
- .450/400 Nitro Express
- Available in 3-inch and 3¼-inch case lengths. A 400-grain bullet at around 2,150 fps. The lightest of the classic NE family, it offers a significant step up from the medium bores with somewhat less recoil than the .470 NE. Well suited to buffalo and lion; marginal for elephant by most professional hunters' standards.
- .404 Jeffery
- Technically a rimless cartridge designed for bolt-actions, but chambered in some double rifles. A 400-grain bullet at around 2,125 fps. Less common in doubles than the rimmed NE cartridges but respected for its performance and the relative availability of ammunition.
- .470 Nitro Express
- The most widely used dangerous-game double rifle cartridge in the world. A 500-grain bullet at around 2,150 fps. Introduced in 1907 after India banned the .450 NE, it became the standard against which other NE cartridges are measured. Ammunition is available from multiple manufacturers and is stocked by outfitters across Africa. For a first dangerous-game double, the .470 NE is the default recommendation of most professional hunters.
- .450 Nitro Express
- The cartridge the .470 NE replaced in many markets. A 480-grain bullet at around 2,150 fps. Banned in India and Sudan in 1907 due to its similarity to military ammunition, which drove hunters toward the .470 NE and others. Still available and still used, but the .470 NE has largely supplanted it in the field.
- .500 Nitro Express
- The cartridge this journal is built around. A 570-grain bullet at around 2,150 fps. More recoil than the .470 NE, more energy, and a heavier rifle to carry it. The .500 NE is the choice of hunters who want the most capable cartridge in the classic NE family without moving to the large bores. It is entirely adequate for elephant, and for buffalo and lion it is more than adequate.
The large bores: .577 and .600
Above the .500 NE sit the large-bore stopping cartridges — the .577 Nitro Express and the .600 Nitro Express. These are specialist tools, not general-purpose hunting rifles. They were designed for stopping a charge at very close range, where penetration and shock matter more than precision. The .577 NE drives a 750-grain bullet at around 2,050 fps. The .600 NE drives a 900-grain bullet at around 1,950 fps. Both produce recoil that requires serious preparation and practice to manage, and both are chambered in rifles that are heavy by any standard — typically 14 to 16 pounds.
For most hunters, the large bores are a curiosity rather than a practical choice. Professional hunters who work in elephant country and face the possibility of a charge at arm's length have a legitimate use case for them. For a first double rifle, or for a hunter whose primary quarry is buffalo and lion, the .500 NE is the sensible upper limit.
Choosing a calibre family: the practical questions
The right calibre for a double rifle depends on three things: the game you intend to hunt, the recoil you can manage comfortably, and the ammunition you can source reliably. All three matter, and none can be ignored.
The dates in the table are worth a moment's attention. The .500 Nitro Express, introduced in 1890, is the oldest cartridge here — predating several that were designed to replace or supplement it. A cartridge that has remained in production for over 130 years, with rifles still being built for it and outfitters still stocking it, has earned that longevity against real game in real conditions. When I read the inscription on my own barrel, I am reading a designation that predates the Boer War. That continuity matters to me, though it need not matter to you.
| Calibre family | Introduced | Typical quarry | Recoil character | Ammunition availability |
|---|---|---|---|---|
| 9.3x74R | c. 1900 | Plains game, leopard, lion, buffalo | Moderate — manageable all day | Good — stocked widely in Europe and Africa |
| .375 Flanged NE | 1912 | All dangerous game to elephant | Moderate — the legal minimum in many countries | Good — widely available |
| .404 Jeffery | 1905 | Buffalo, lion, leopard, elephant | Firm — less than the classic NE cartridges | Moderate — bolt-action origins; fewer double-rifle loads available |
| .416 Rigby | 1911 | All dangerous game including elephant | Firm to heavy — sits between medium and classic NE | Moderate — bolt-action origins; specialist double-rifle loads |
| .450/400 NE | 1902 | Buffalo, lion, leopard | Firm but manageable | Moderate — fewer manufacturers than .470 NE |
| .458 Lott | 1971 | All dangerous game including elephant | Heavy — comparable to .470 NE | Moderate — primarily bolt-action; uncommon in doubles |
| .470 NE | 1907 | All dangerous game including elephant | Heavy — the standard dangerous-game double | Excellent — the most available NE cartridge |
| .500 NE | 1890 | All dangerous game including elephant | Very heavy — requires practice | Good — available from major manufacturers |
| .505 Gibbs | 1911 | All dangerous game; elephant specialist | Very heavy — comparable to .500 NE | Limited — specialist suppliers; bolt-action origins |
| .577 NE / .600 NE | 1900 / 1903 | Elephant, stopping charges | Severe — specialist use only | Limited — expensive, few sources |
| .700 Nitro Express | 1988 | Elephant; stopping charges at extreme close range | Extreme — the most powerful sporting cartridge in production | Very limited — Holland & Holland only; bespoke orders |
On recoil
Recoil from a .470 NE or .500 NE double rifle is not like recoil from a bolt-action. The double fires both barrels in rapid succession if needed, and the combined effect — even from a single barrel — is substantial. A rifle that fits well, that you mount correctly, and that you shoot from a proper stance is manageable. A rifle that does not fit, or that you flinch away from, is not. Before committing to a calibre, shoot it. If you cannot access the actual cartridge, shoot the closest available equivalent and be honest about what you find. There is no virtue in choosing a cartridge that you cannot shoot accurately under pressure.
On ammunition availability
The .470 NE is the benchmark for ammunition availability in the dangerous-game double rifle world. Kynoch, Hornady, Federal, and several smaller manufacturers load it. Outfitters across Africa stock it. If you are hunting in a remote area and your ammunition is lost or damaged in transit, the .470 NE gives you the best chance of finding a replacement. The .500 NE is well supported but not as universally stocked. The .450/400 NE is available but from fewer sources. The large bores are expensive and difficult to source outside specialist suppliers. Ammunition availability is not a reason to choose a calibre you cannot shoot well — but it is a real consideration for a hunting rifle rather than a range gun.
- Medium bores (9.3x74R, .375 Flanged) — versatile, manageable, suited to mixed hunting including dangerous game.
- Classic NE cartridges (.450/400, .470, .500) — the core of the dangerous-game double rifle world; heavy bullets at moderate velocity.
- Large bores (.577, .600) — specialist stopping cartridges; not a first choice for most hunters.
- The .470 NE is the default recommendation for a first dangerous-game double: proven, widely available, and well supported.
- Recoil must be tested before committing to a calibre — a cartridge you cannot shoot accurately is not a safe choice.
- Ammunition availability in the field is a practical constraint, not a theoretical one.
My .500 NE is not the cartridge I would recommend to someone buying their first dangerous-game double. I would recommend the .470 NE — better ammunition availability, slightly less recoil, and a larger pool of used rifles to choose from. I chose the .500 NE because I had already shot one, knew I could manage it, and found a rifle I trusted at a price I could justify. That sequence — shoot first, choose second — is the right order. The calibre families give you a framework. Your own experience with recoil and your honest assessment of the hunting you intend to do give you the answer.