I just shoot and really don't pay attention to the mechanics of the guns. The other thread on belted magnums got me wondering- why is there a belt on a belted magnum?

The original H & H mags (300 & 375 ) both had/have gently sloping shoulders which do not (in theory) provide much space/area/ability to/for head spacing. The belt provided a way to headspace these---similar to a rim on a rimmed (NE) cartridge.

The original H&H rounds were not even considered magnums nor were even called magnums if memory serves me correct.

From what I've been told is they had a belt to allow use in a double rifle...that's it

Several cartridges were made using these cases for many many years.....this is why several "magnums" have a belt

It serves no purpose outside of what I've outlined IMO

Texas Killartist is correct. The 375 H&H, being rimless with the long, tapered case and low shoulder, needed a way to positively headspace. Hence the adding of the belt.

Ted is right about the cartridges being made from the original 375 H&H (338 WM, 7mm RM, etc.) and left the belt on the case. Come to find out, these necked down versions are easily head spaced on the shoulder, effectively negating the belt. Hence hearing the argument nowadays 'what good is a belt'? With the advent of modern, stable powders, you could even headspace a 375 H&H on the shoulder.

Belts aren't related to the function of double rifles. Virtually all doubles are flanged/rimmed to allow for correct head spacing and extraction. Just like a lever action rifle. There are a few doubles out there made for rimless cartridges but not many.

Like Heelr said, although, oddly enough Holland's .240 Apex has a belt...yet if you look at the cartridge doesn't need it.

One US "wildcat" that WOULD benefit from a belt is the .400 Whelen.

"Belted" cartridges are not synonymous with "magnum". The term "Magnum" bears no specific metric/measurement to a given cartridge and is just a label.

I have always heard that the belt was there for headspacing as well.

It was an attempt to do so that would work with magazine rifles without causing the issues that rimmed cases did.

As far as being able to headspace off of them, it does work fine...but as some note it often results in shortened brass life if you reload doing that. Resizing on the shoulder works well as long as you are using one rifle, some have the shoulder in a bit different position so ammo interchangeability can be hurt if you are trying to prolong case life.

quote:

Originally posted by thirdbite:
Are the tolerances on belts precise enough to actually be able to control headspace? I had always understood that belted cartridges should be headspaced on the shoulder as the tolerances on the belt don't allow proper headspacing.

That and with the variances/conditions of reamers used when chambering rifles you might never be able to headspace on the belt.

I neck size the brass on my 375 H&H and 7mm RM (only one rifle for each), so don't worry too much where the round headspaces.

I think the transition from rimmed cases was the primary answer, for the Brits. Mauser bolt rifles in rimless cases had been around for several years.

The long, gentle taper and lack of a real (as we know it) shoulder are a product of the Double and Single shot rifles with their ease of loading under stress. Like one of the Dangerous Game Five closing on you at full speed.

quote:

"Belted" cartridges are not synonymous with "magnum". The term "Magnum" bears no specific metric/measurement to a given cartridge and is just a label.

Yes. I've come back to "dip" into this thread again. From my side of the Atlantic.

One of the early high power cartridges was the .280 Ross. Neither belted nor labelled "magnum".

We've also, probably, been the ONLY world power that used a belted cased cartridge as a true widespread issued service weapon?

The .55" Boyes Anti-Tank rifle.

And, of course, the most "odd" belted pistol cartridges of BSA. The .34 BSA. That never did get much beyond prototype stage.

quote:

Originally posted by thirdbite:
Are the tolerances on belts precise enough to actually be able to control headspace? I had always understood that belted cartridges should be headspaced on the shoulder as the tolerances on the belt don't allow proper headspacing.

My understanding of the belt.

Dont confuse best practices for reloading belted cartridges with why the cartridge was designed with a belt.

The belt was to permit reliable headspacing with no consideration to case stretching or reloading of the case.

When you reload belted cases, you can prolong case life and postone case head separation by setting to your resizing die to headspace off of the shoulder and not the belt.

What a bunch of internet know-it-alls.


The obvious answer is usually correct...a belt was needed to keep its pants up.

Frank,

you strike me as the kind of guy who would wear both suspenders, and a belt. To keep your pants up...

Correct me if i'm wrong but wasn't the 375 H&H known as 'Hollands .375 rimless nitro express?

The .300 and .375, along with their predecessor the .400/.375, were loaded with cordite, hence the tapered case shape (the cordite was loaded into the case prior to final case forming). The belt was needed on the .400/.375 and was carried over on the .375 and .300. SAAMI specs for virtually all belted cases call for headspacing off the belt, not off the shoulder.

The original name was the .375 Belted Rimless Nitro Express. A version for double rifles (loaded to lower pressures) was called the .375 Flanged Magnum.


.

Ya I'm going with the "no place to hook the suspenders"
As to Idaho's comment: my dad always said "never trust a man who wears both a belt and suspenders as they could not even trust their self."

Perhaps on a point of order:

The first Belted cartridge was a US invention during the American Civil War and not British as popularly proposed.

The inventor was Sylvester Howard Roper of New Hampshire, a former machinist with the Singer Sewing machine factory who around 1866 designed a revolving magazine rifle and shotgun with a steel belted cartridge. At the time of this design he was working for the Springfield Armoury

The purpose of the belt was to headspace on as the cartridge was essentially a straight walled steel case. This head spacing function is described in the original patent.

quote:

The inventor was Sylvester Howard Roper of New Hampshire, a former machinist with the Singer Sewing machine factory who around 1866 designed a revolving magazine rifle and shotgun with a steel belted cartridge. At the time of this design he was working for the Springfield Armoury

I searched Mr Roper's patents and could not find the steel belted cartridge claim.

I have a set of reamers(roughing and finish) that I ahd sepcial made for a customers order many years ago...they are 338 Win. Beltless Magnum.

It worked great in the M98 action I built his rifle on, it allowed one more down in the box and fed beautifully with very little work. Headspaced like any other shouldered cartridge. Everything else was the same, bullet selection, powder, primers, et. al. Just had to turn the belt off the brass.

Those reamers have cut precisely one chamber but I've always thought it was a good idea and if I ever built myself a 338 magnum that is what I would use. I have a 338-06 that works just fine, so I will probably never build one.

Re Frank's input about a belt being necessary 'to keep its pants up'. There's something in that.

After all it's cartridges without adequate shoulders that most need a belt. 'Cos if these cartridges had adequate shoulders then they wouldn't need a belt but could use suspenders.

Yes. There's something in this. But can Frank help with this?

Why do rimfire cartridges make bad painters and decorators do a shoddy job? Is it because they don't use primers? But how could they? Having no pockets to keep them in?

Must go. The nurse is coming. He says its time for my medication...

Ah. Holland's .375. Beware there's two (and I don't mean the 'flanged' double rifle version of the magazine rifle cartridge).

There's the .375 Holland and Holland Nitro Express (only ever a rimmed cartridge it dates from pre-1900) and the .375 Holland and Holland Belted Rimless Magnum. The Nitro Express being a shorter 2 1/2" cartridge.

.375 Nitro Express

I'll stand corrected on the exact correct name but Holland's .375 NE isn't the same as Holland's .375 Magnum. The 'tab' 'Nitro Express' and 'Express' usage being very much of the pre-1907 Edwardian era. The latter .375 Magnum is still currently made and chambered. The former is, effectively, obsolete but was used in some Lee Enfield sporting rifles and, I nearly bought one some thirty years ago, some double rifles.

I have not studied cartridge design as much as I have studied action design, but I am of the opinion that the belt does not do much, if anything, to increase the strength of the case head or prevent cartridge rupture. Because the case headspaces on the belt, there will be a gap between the belt and the chamber. That gap is covered by the sidewall of the case and that sidewall is not as thick as a standard case head. I have not sectioned a belted magnum, but I believe that statement to be true.

From what I have read, these early belted rounds were not high pressure which is a good characteristic. High pressure is actually undesirable from a function perspective. If you can do the same job at low pressures, you are better off doing it. Pressure only causes problems, and those problems occur sooner and faster as pressures increase. A problem would be, sticking extraction due to heat. Temperatures raise the combustion pressure of gunpowder, and something operating at 60,000 psia at room temperature will easily be operating at 70,000 + psia at temperatures above 100 F.

I am not a fan of the belted magnum design, it would be interesting to know exactly why H&H came up with it, but it could have been marketing driven more than function driven. Of course once the belted magnum was associated with expensive British rifles, and the British nobility, you can see how that snobbery aspect carried over as a marketing asset to Weatherby and others who used the parent case.

Slamfire,
The belted case is no stronger than an ordinary case, the reason is because the belt lies over the solid web. It doesn't provide any extra strength the web/ case wall junction.
Also, the belt stops the case moving forward from the firing pin impact, just as the shoulder does on a normal case.
You are incorrect regarding the 375 being loaded to low pressure, the original cordite loads were quite stiff in the 375 H&H for the time period.
There's a simple reason why the belt remains, there were few cartridges that were similar in size, that's why it was used to blow out, shorten, straighten etc etc.
You may not like the belt due to some ill conceived notion, it isn't a problem if you ignore it when reloading, by that, I mean to headspace off the shoulder after the first firing. I have heard it said so many times that the belt causes inaccuracy, tell that to the many records geld by the 300 Win Mag, it has a belt AND a neck that is too short. It's the most accurate cartridge I own, it runs rings around my 338 Edge, which is supposed to be more accurate because it doesn't have a belt!
All of my belted magnums are accurate, including Weatherby chamberings I use.

Cheers.

The original intent of the belt was not to strengthen the base but to act as a head spacing rim.

The reason for this was because early rifle chambers were poorly cut.

Modern belted cases headspace on the Shoulder.

The Roper Belted case for the 41 cal Roper rifle was a straight wall steel case. Not to be confused with the Roper Shotshell case for the Roper revolving shotgun of 1866 which had a massively rebated rim.

The rifle was essentially the same gun as the shotgun as described by patent 53881 dated April 10, 1866 but with a rifled barrel.


The Accles "double belted" case of 1889
( Birmingham) specifically cited the front belt to prevent the case from going to deep in the chamber ie headspacing and the rear to act as a extraction rim

The Roth belted case of 1892 ( George Roth of Vienna) stated the same reason for design in their patent.

The 41 Roper was a straight wall case thus by definition had to headspace on the belt.

Bobstruck of Olin recently ( 1980's) revisited the belted shotshell case for a combat shotgun.
In this instance the belt prevents the case from being chambered in a commercial shotgun and more importantly the head of the case with it's belt is unsupported by the chamber In this case unsupported head is strengthened by the belt.

This because these specific combat shotguns are full auto loading and having a head that is not enclosed by the chamber and this facilitates faster cycling through the gun in full auto mode
The Olin Patent actually references the original Roper Patent of 1866

I happened on a thread in a Continental forum recently that was discussing the rivalry between the 9.3x62 and the 375 H&H magnum. One writer claimed the .375 mag was designed expressly to counter the smaller cartridge and that the term 'magnum' was claimed because the velocity exceeded 2500fps. This would make no sense in reference to British black-powder cartridges that had previously been tagged with the magnum term, of course.

An Australian firearms writer of half a century ago claimed the term magnum applied to cartridges that pushed heavier bullets than usual in a given bore size. I can't quite see how this would apply to the 256 Winchester, however. In the end, I guess a magnum is whatever the originator says it is.

good post ALF!

It may even be just the shape of the case...like a "magnum" of champagne. But what then of the .450/.577 M-H?

Here is an illustration of that .41 Roper rifle cartridge Alf has discussed above, along with a Roper shotgun cartridge:



1866 for the American invention, a reloadable steel case charged with BP and a percussion cap.



From Hoyem, Vol. 3, pp. 119-122, quoted for book review purposes, a good book:

.375 - 2-1/2" (.375 or .370 FLANGED NITRO EXPRESS):
"This cartridge is believed to have been developed around the turn of the century, loaded with 40 grains of smokeless powder and a 270-grain jacketed bullet. The cartridge with .375 or .370 headstamp has the same charge and the bullet diameters are identical. Used in light double rifles, single shots, and even the Lee magazine rifle, it was still around after WWII. The Holland & Holland label is black on white, the .370 box is pale green with black label." (loaded with Cordite by H&H, London and Kynoch Limited, Birmingham)

.400/.375 BELTED NITRO EXPRESS (.400/.375 HOLLAND & HOLLAND:
"This cartridge appeared in 1905, the first of Holland & Holland's belted case rifle loads. The charge was 43 grains of cordite and a 270-grain bullet. It was used for the most part in bolt action magazine rifles ... This round was somewhat under-powered for large game."

.375 RIMLESS NITRO EXPRESS (9.5x57 MANNLICHER SCHOENAUER:
This cartridge is the British loading of the 9.5x56 Mannlicher-Schoenauer of Austrian origin ... 43 grains of smokeless and a 270-grain bullet ..."

.375 BELTED RIMLESS MAGNUM (HOLLAND'S .375 MAGNUM RIMLESS):
"Introduced in 1912, this became the most widely used of all the Holland & Holland belted case designs. It is still available from U.S. and continental European makers. Three loads were originally offered: 58 grains of smokeless with 300-grain bullet; 61 grains with 270-grain bullet; 62 grains with 232-grain bullet (sic) ..."

.375 FLANGED MAGNUM (.375 HOLLAND & HOLLAND FLANGED):
"Holland & Holland brought out this cartridge in 1912 as the rimmed version of the preceding cartridge for double rifles. The charges were conservative to avoid high pressures, but the bullet weights were the same. Loads were 56 grains with 300-grain bullet; 59 grains with 270-grain, and 60 grains with 235-grain (sic) ..."

The "magnum" term applied to cartridges was (and still is) just marketing hype for "more velocity" like "more wine" in the magnum-sized wine bottle versus the standard:
This funny from the other thread deserves repeating:



The belt has nothing to do with a magnum. It is an antique headspacing method as discussed in previous posts above,
as useful as suspenders and a belt (with exceptions for specific firearms) to hold up your pants, aye.

Where the belt meets the case body, that is a stress riser (90-degree angle there), so a beltless case head can certainly be made stronger at that distance from the boltface, for whatever that is worth, or not.

Riflecrank Internationale Permanente
NRA Life Benefactor and Beneficiary
https://home.nra.org/

I agree that the belt was used as a head spacing device.
If head spacing was all he belt was for, making it a rimmed case would have been just as usable.
The belt being thicker than a rim helped in a magazine fed rifle. rims if not aligned properly can overlap and prevent feeding a round from the magazine.
The thicker belt was used to prevent this over lap of rims to improve feeding from the magazine.
Leo

quote:

Originally posted by ALF:
Modern belted cases headspace on the Shoulder.

Like the .458 Winchester and .458 Lott?

for ease of headspacing consistency

quote:

Originally posted by ALF:
Modern belted cases headspace on the Shoulder.

*COULD* but not a SINGLE one does, according to CIP and SAAMI

many gunsmiths even cut the chambers to do this, but NO, without reservation, does a "modern" belted round headspace on the shoulder -- even the 400 and 465HH, as well as the 450 marlin -- all use headspace gauges on the BELT.

there is no point is discussion on that -- and now, within a week, alf's post will disappear

quote:

Originally posted by jeffeosso:
for ease of headspacing consistency

quote:

Originally posted by ALF:
Modern belted cases headspace on the Shoulder.

*COULD* but not a SINGLE one does, according to CIP and SAAMI

many gunsmiths even cut the chambers to do this, but NO, without reservation, does a "modern" belted round headspace on the shoulder -- even the 400 and 465HH, as well as the 450 marlin -- all use headspace gauges on the BELT.

there is no point is discussion on that -- and now, within a week, alf's post will disappear

I think jeff is correct.Check the amount of stretch in firing a factory load in a 300 H&H or 300 Win Mag. Not uncommon for those shoulders to move forward on first firing.

The tapered cases of the 300 and 375 H&H were easily loaded with cordite, the powder of the day. The tapered design of the cases fed slickly and easily from the staggered box magazine of a Mauser-tpe bolt action.

The belt served as a "stop" to headspace and withstand the heavy blow of the firing pin to help insure reliable ignition.

Headspace off the belt left some "slop" in the front of the chamber to allow reliable chambering under dirty tropical conditions (or elsewhere),where rifles were subject to real abuse for lengthy periods of time.

The taper of the case also helped with primary extraction, when the bolt handle is lifted in a Mauser system, moving the case slightly to the rear to break away from the chamber walls.Tapered case break away more easily than straight walled cases.

The Brits were "function" mavens since the H&H rounds were used world wide in every conceivable environment. H&H was not concerned with reloading cases. To them that was trivial pursuit. Their rifles and ammo were intended for the biggest and baddest animals in the world.

The 400 and 465 are of similar design. It's no accident.

The belt may not be required today, but hurts nothing either in hunting rifle as empirical results show.

I used to like the ability to make 300 H&H into 300 Weatherby by firing the rifle. Those cases headspace on the belt, making fire forming a piece of cake.

I wasn't there but something tells me the H&H belted cases were easily available for fire forming back when many modern melted cases were developed.

The chambering of the M70 for 300 and 375 H&H back in the 1930s started the belted magnum trend in the 1930's.Roy Weatherby and others wildcatted the belted brass and factories followed suit later.

You can't blame them as a perfectly good beltless case that had been around for years (the 30 Newton), had fallen flat on its face.