What Are Belted Magnum Cartridges?

In an article published on The Shooter’s Log entitled “The Evolution of Modern Ammunition” published on August 8, 2022, Dr. Mike commented:

“Wonderful and informative article. Could you also explain what the term “belted case” means? Thank you and please keep further such articles coming.”

.375 Holland & Holland Safari rifle
One of my favorite (and well used) .375 Holland & Holland Safari Veterans. Note the Belt it made famous.

I was slightly confused by his comment. At no point in the article did I mention belted cartridges. However, I did respond to his query with the following comment that was posted in the Comments section.

“In answer to Mike’s question: Belted cartridge design was introduced by the British firm of Holland & Holland for their proprietary calibers, where the chamber is shaped to seat the forward face of the belt. Because of the their proprietary shape it was not possible to provide proper headspacing off the shoulder for their new cartridge design. Holland’s solution was to add a belt around the cartridge body similar in function to the rim of a rimmed cartridge case head. Look for a future article by me that will cover belts and headspace in more detail. Thank you for your interest.”

And so, the time has finally come for me to address what “belted case” means in more detail.

A Bit of History

The first cartridge to employ a belted case was the .375 Velopex which debuted in 1905 and was also known as the .400/375 Belted Nitro Express. The belt itself was not intended to be anything but a means of headspacing the cartridge by acting like a small rim. It was designed to allow for much smoother feeding from a box magazine than any rimmed cartridge of the era could.

The belt’s main reason for existing is a very specific technical one that is based on the fact that bolt-action magazine-fed rifles function their best with rimless cartridges. Rimless cartridges, however, need a fairly substantial shoulder on their case to headspace properly. The reason for that is because the case mouth can not be relied upon, because the bullet is most often crimped with commercial factory ammo.

7mm Remington Review cartridge
The 7mm Remington Magnum features a strong belt, sharp shoulder and relatively short neck. It is a very powerful and overall efficient cartridge.

Complicating the issue in the early 1900’s was the use of cordite as the primary propellant of the time. Cordite was an early smokeless propellant with a fairly high nitroglycerin content. Nitroglycerin came in little sticks about the size of a pencil lead that was cut to a length that fit between the inside of the case head and the base of the bullet. Because of its design you could not pour it like other powders into the case, you had to instead insert a bundle of sticks into the case.

The need to insert the cordite bundles into the case resulted in a substantial number of British cartridges designed with cases that have shoulders that are either narrow in width (like the .375 H&H) or a shallow angle (like the .300 H&H). That is why it is necessary for the 90-degree forward edge of the belt to provide the surface for the cartridge to headspace off, while supporting the case for the firing pin strike to provide reliable ignition and smooth feeding in magazine rifles.

The term ‘belted magnum’ or ‘belted case’ refers to any cartridge with a shell casing that has a pronounced “belt” around its base that is positioned just past the extractor groove. The belted case design was originally conceived and designed by the British gunmaking firm of Holland & Holland for the purpose of headspacing certain powerful cartridges of the day.

Long, powerful, rifle cartridges without a shoulder — especially magnum rifle cartridges — could be pushed too far into the chamber. That could cause a catastrophic failure of the gun when fired because of the excessive headspace caused by not having a shoulder to rely on. Holland & Holland deduced that the addition of a belt surrounding the circumference of the case would prevent the possibility of over-insertion and excess headspace, while allowing for smoother feeding from a box magazine compared to that of a rimmed cartridge.

Dik Dik (left), Giraffe (right)
When on Safari in Africa, one never knows where or what one will encounter from the smallest Dik Dik to the tallest giraffe or anything in between, with a .375 Holland & Holland Magnum in your hands you can easily take on anything.

Magnum

I suppose at this point it might be appropriate to also explain the use of the word “magnum” as it applies to cartridge designations. Initially, large-bore hunting rifles, (known as elephant guns) used cartridges with the appendage of Nitro Express… Example: the Rigby .450 Nitro Express. The use of the word “express” was coined by James Purdey in 1856, and was taken from the large, fast, or “express” trains of the day to emphasize the performance and size of the cartridges used in his double rifles.

The use of the word “nitro” came from the cordite, which is composed of nitrocellulose and nitroglycerine that was the propellant used in those cartridges. The term ‘Nitro Express’ caught on and was used by other makers of rifles and cartridges capable of taking all Indian and African dangerous game. It was in 1898 that John Rigby & Company unveiled his previously mentioned, .450 Nitro Express which started the beginning of the modern big game cartridge era.

In 1912, when Holland & Holland introduced its revolutionary .375 H&H Belted cartridge, it wanted a designation that would set it apart from the current field of cartridges and coined the term “magnum.” The word “magnum” is a derivation of the Latin word magnus which means “great.”

In the wine making industry, magnum refers to a larger-than-normal size of a bottle of wine or champagne. In the world of cartridges, it has come to mean a cartridge with a greater level of performance. And so it was that the classic .375 H&H Belted Magnum was born.


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Some additional comments about the .375 H&H might be appropriate at this time for those who might be interested. It is considered by many to be one of the most useful all-round rifle cartridges ever designed. The most common bullet weight available for the .375 Holland & Holland Magnum is 300 grains.

In many African countries, the .375 H&H is the legal minimum caliber acceptable for hunting dangerous game. The .375 H&H is the preferred all-round caliber that is chosen by African guides, professional hunters, and dangerous game cullers as their choice — if they could only have one rifle. Alaskan guides have a similar preference for hunting the large brown and polar bears in their areas.

Two lioness in the Kalahari
Something I can guarantee you don’t want to stumble upon unless appropriately armed.

One of the things I like most about the .375 H&H Magnum is that unlike many other calibers, .375 H&H Magnum rifles provide, for all intents and purposes, practically the same point of impact over a wide range of bullet weights at hunting distances out to 200 yards. This simplifies a hunter’s choice in selecting different bullet weights. If you pre-sight the rifle for different bullet weights prior to a hunt, based on the game hunted, you can change to a different bullet weight in the field and not have to worry about scope or sight adjustments. It is those types of advantages that also contributed to the popularity of the .375 H&H Magnum among serious hunters.

I have personally used the .375 H&H on everything from small to medium game, as well as large, thick-skinned dangerous game while on safaris in Africa and have found it to be versatile and effective. Other calibers that I have used in Africa to conform to the required legal minimum when hunting large and thick skinned Dangerous Game have included the .416 Rigby, .458 Lott, .470 Nitro Express and Holland & Holland .500/465 Nitro Express.

All acquitted themselves admirably. However, for my money (unless you are a P.H. and need clean up a client’s bad shot), the .375 H&H Magnum will do everything the large calibers will do but with less recoil to contend with and more long range reach. As I have said before… It is and always will be about shot placement and penetration.

Karamojo Bell in 1915
Karamojo Bell in 1915.

As Walter Dalrymple Maitland Bell (8 September 1880 – 30 June 1954), proved by harvesting most of the 1,011 elephants during his career using a Rigby-Mauser rifle chambered in the 7×57 caliber that he made famous. He used the standard military 173-grain, round-nosed, full metal jacket load, but he pulled the bullets and turned them around, so the flat solid end provided deep straight penetration. He was also known as Karamojo Bell after the Karamojo region of Uganda where he hunted and was a truly colorful and larger than life character of the period. I recommend reading about him.

7x57 chambered Custom Ruger #1
My 7×57 chambered Custom Ruger #1 is a favorite, but I don’t think I would feel comfortable confronting a Bull Elephant at spitting distance with it like Karamojo Bell did 1,011 times.

Common Belted Cartridges

The addition of a belt has been used on many popular calibers since its creation, and includes the following:

.244 H&H Magnum .257 Weatherby Magnum .264 Winchester Magnum
.275 H&H Magnum* 7mm STW .270 Weatherby Magnum
7×61 Sharpe & Hart Super 7mm Weatherby Magnum 7mm Remington Magnum
.300 Winchester Magnum .300 H&H Magnum .308 Norma Magnum
.300 Weatherby Magnum .338 Winchester Magnum .358 Norma Magnum
8mm Remington Magnum .340 Weatherby Magnum .375 H&H Magnum
.375 Weatherby Magnum .400 H&H Magnum .416 Remington Magnum
.458 Winchester Magnum .458 Lott  

I hope that I have addressed the question of “Belted Magnums” in this article to everyone’s satisfaction. However, if you have a question, or a fact to add, please sound off in the Comment section.

Source link: https://blog.cheaperthandirt.com/what-are-belted-magnum-cartridges/?utm_source=rss&utm_medium=rss&utm_campaign=what-are-belted-magnum-cartridges by Ed AKA “The Real Most Interesting Man in The World” LaPorta at blog.cheaperthandirt.com