magnum belts

[huntokanogan]

This may be a rather dumb question to some. I don't know the answer and thats why I joined this forum...to gain firearm knowledge. So please help me with an answer.

-Why are magnum cartridges belted?

-With the popularity and effectiveness of the RUM line, are we going to see belted magnums dissapear in the future? Are the RUM cartridges considered true magnums since they have no belt?

 

[royinidaho]

This may be a rather dumb question to some. I don't know the answer and thats why I joined this forum...to gain firearm knowledge. So please help me with an answer.

-Why are magnum cartridges belted? Thicker brass allowing higher pressures.

-With the popularity and effectiveness of the RUM line, are we going to see belted magnums dissapear in the future? Nope . . . cartridges like the 7mm REM Mag and 300 Win Mag will keep them around for a long time. In a well manufactured rifle there are no down sides to a belted case. Are the RUM cartridges considered true magnums since they have no belt? Oh yeah. . .

Just my thoughts.....

 

[boomtube]

"Magnum" simply means large, as in comparison to others in it's class. The belt on rifle cartridges, as such, is not a part of that.

The first magnum was one of the H&H line, don't remember which, .375 I think. It has a long tapered body and shoulder that demanded a rim or belt to insure firing pin impact didn't drive it too far forward and cause a hang fire. Never the less, the idea was easy to use in advertizing so when American makers started with the magnum craze with the .300 Weatherby and Winchester, they also used belted cases to take advantage of the popular concept but they also have sufficent shoulders to negate the need for a belt. A belt actually adds no particular case strength advantage at all.

A belt actually shares the same difficulty in a bolt rifle as most rimmed cases - it eats magazine space for no purpose. That is NOT an advantage, so the more recent designs have abandoned the belt while retaining the head size. The newer fatter cases can hold more powder in a same length chamber.

The popular old magnum rounds will survive a long time because they do good work but I doubt any new magnum rounds will be made with the pointless belts, that fad has finally passed.

 

[Bart B]

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 when they were introduced together in August, 1912.

This second belted case design was later used with the .300 H&H Magnum (Winchester, 1925), and has been modified as the basis for "Magnum" cartridges developed by other arms manufacturers. Weatherby used the case as the basis for their .257, .270, 7 mm, .300, .340, and .375 Weatherby Magnum cartridges. Norma Projektilfabrik A/S shortened the case as the basis for their .308 and .358 Norma Magnum cartridges. Winchester Repeating Arms Company used similarly shortened cases for their .264, .300, .338, and .458 Winchester Magnum cartridges. Remington Arms used the case for their 6.5 mm, 7 mm, 8 mm, and .350 Remington Magnum cartridges.

That belt allowed the same cartridge to be used in both double rifles and box magazine bolt action rifles.

 

[BigSkyGP]

If I have the story of the .308 Norma Mag right. The idea behind the length of it was that military arms of the era having 30-06 length actions could be rechamberd and the average rifleman could aford to have a magnum chambered rifle.

Then Winchester stormed the market with their .300 Win Mag and pretty much washed them out.

 

[Bart B]

If I have the story of the .308 Norma Mag right. The idea behind the length of it was that military arms of the era having 30-06 length actions could be rechamberd and the average rifleman could aford to have a magnum chambered rifle. Then Winchester stormed the market with their .300 Win Mag and pretty much washed them out.

Yup. That's right. Here's more detail on the man, time and place.

In the late 1940s Nils Kvale at Norma, Sweden, designed a wildcat called 8mm Kvale. It was intended for use in the German surplus 8mm Mauser M98 that flooded the American market after the war and was therefore nicknamed 'Poor Man's Magnum'. Kvale used the case from the .300 H&H Magnum and reduced the rim diameter so it would fit the bolt of a Mauser M98. The experiences he made from this cartridge was put into the .308 and .358 Norma Magnum.

Years earlier in 1913, Charles Newton designed the .30 Newton, a rimless bottleneck case of the same case capacity and performance as the .308 Norma Magnum. A much better round for reloading and accuracy as it didn't have that belt which too often caused problems. But the H&H belted cases were thought to be better and stronger by most folks so they prospered while the better Newton design fell by the wayside.

In the 1960's, a similar case was designed by a US military marksmanship unit called the .30 FBI intended to be used in US government sniper rifles; nothing more than a .30-.338 (AKA .30 Belted Newton) shortened about 1/8th inch and its belt turned off to make a short, fat rimless bottleneck case. Very accurate and easy to reload, it never caught on.

 

[Trickymissfit]

"Magnum" simply means large, as in comparison to others in it's class. The belt on rifle cartridges, as such, is not a part of that.

The first magnum was one of the H&H line, don't remember which, .375 I think. It has a long tapered body and shoulder that demanded a rim or belt to insure firing pin impact didn't drive it too far forward and cause a hang fire. Never the less, the idea was easy to use in advertizing so when American makers started with the magnum craze with the .300 Weatherby and Winchester, they also used belted cases to take advantage of the popular concept but they also have sufficent shoulders to negate the need for a belt. A belt actually adds no particular case strength advantage at all.

A belt actually shares the same difficulty in a bolt rifle as most rimmed cases - it eats magazine space for no purpose. That is NOT an advantage, so the more recent designs have abandoned the belt while retaining the head size. The newer fatter cases can hold more powder in a same length chamber.

The popular old magnum rounds will survive a long time because they do good work but I doubt any new magnum rounds will be made with the pointless belts, that fad has finally passed.

Actaually I think the term "magnum" started over here. Most of the so called magnums were called express cartridges long before the term magnum. I also think maybe Ackley may have been one of the first to use that term, but doubt he was the first
gary