Here is a posting that I borrowed from another site that helps with the understanding and the timelines osurrounding the 8mm cartridges.

The rise and fall of calibres are sometimes as a result of specific circumstances and not because they did not perform well enough. In the sporting or hunting world, we see clearly the preference of the American/British group favouring imperial calibres, whilst in Europe they like their metric calibres. However there are a few exceptions today, such as the ever so popular 7 mm Remington Magnum in the USA. The goal of this article is to give an overall view specifically on the 8 mm family of cartridges and why they are not so widely used anymore. Let us look at 2 standard calibres, the 8 x 57 mm and the 8 x 60 mm, and 2 magnum calibres, the 8 x 68 mm and the 8 mm Rem Magnum. For brevity sake, I have ignored the other less common 8 mm offerings, as well as all the 8 mm wildcats.

Germany fought 2 world wars with the 8 x 57 mm Mauser (all the above mentioned calibres were hunting cartridges ) ... quite remarkable, it speaks of excellent design and service by this calibre. The 8 x 57 mm Mauser was adopted as the German service rifle way back in 1888 - this was the date when it all began for the 8 mm family that was to follow. Initially it had a diameter of .318" but it was later changed to .323" in 1905. Little could they foresee the major impact that their 1888 design would have on the gun world. It was used both by the military and by hunters.
Hitler denounced the Treaty of Versailles in 1934 and started with rapid re-armament in June 1935. This time, Germany went to war with the short version of the Mauser, the Karbiner 98 Kurz - it had a 23.6 inch barrel instead of a 29 inch barrel, as it was too long for trench warfare. Between 1934 and 1945, over 14 million were manufactured. While reloading was slower than with a .303 Br, the German Kar-98ks accuracy was more than enough to make up for it. The Mausers rate of fire was 15 rounds per minute, whereas for the British .303, it was 20 rounds per minute, but with a detachable magazine holding 10 rounds. The Mauser had a magazine capacity of only 5, and so stripper-clips were used to reload quicker, but it was obviously slower than the .303 Br, where one could just insert a fully loaded magazine of bigger capacity. It is interesting to know, that just before the start of World War 2, the Germans replaced the 154 gr spitzer bullet at 2,880 fps with a 198 gr spitzer boatail bullet at 2,575 fps. The main reason was that the bigger powder charge of the 154 gr load produced excessive muzzle flash in the shorter barrel. At the same time they gained better sectional density even though they sacrificed velocity - overall a much more lethal and devastating load ... more momentum and better penetration whilst the lower velocity was less destructive on the bullet. Norma of Sweden still offers ammo for the 8 x 57 mm - a 196 grainer at 2,526 fps, which is ideal for larger antelope at short to medium range. Ironic enough, there was an influx of military 8 x 57 mm rifles into America after the war, and so American ammo manufacturers started to produce ammo for this calibre, but it was totally under loaded and thus its popularity waned against the 30-06 Spr. Here is their load with a 170 gr bullet and it is also happens to be their only load for the calibre:

IMR 4350 --- 43 gr --- 2,315 fps --- 36,800 CUP

After Germany lost the First World War, the Peace Treaty of Versailles limited the number of 8 mm Mauser rifles to a mere 100,000; barely adequate for Germanys defense and sporting fraternity. Strangely enough, sporting rifles of sportsmen were included as well. To comply with the treaty and to save many rifles, it was decided to redesign the calibre, by extending the case to 60 millimeters. This was a minor change, and original barrels were simply re-chambered - everything else remained the same. Amazing you might say, the perception to control or the illusion to control the German Folk. So, the 8 x 60 mm Mauser became the new sporting rifle of Germany and it gained immediate popularity - not much of a choice. Luckily for us, the 7 x 57 mm Mauser escaped the same fate, and continues to be popular even till today in South Africa.

Ballistically, the 8 x 60 mms longer case with its greater powder capacity, was capable of a higher velocity, shooting the same bullet. Its popularity spilled over to Austria, Belgium and France. The sporting version of the Mauser, model A and B, became very sought after amongst hunters the world over. K98 actions were sold to various rifle builders, including the British gun trade. It is estimated that overall, more than a 100 million standard military Mauser 98 actions were built and about 126,400 sporter Mauser actions were built by the Oberndorf factory. Today, the custom built rifle trade is thriving, particularly in Europe - The Model 98 Mauser action is still the undisputed choice for hunting rifles. The ingenuity of the Mauser design is what makes it so special, such as controlled round feeding, secure extraction and its excellent gas deflection system.

The 8 x 60 mm was dropped from production in Germany in the late 1950s, but Belgium were still making it for a good 20 years more. We should bear in mind that the Mauser factory was destroyed after WW2 and Germany was in turmoil. This cartridge was ideal for Europes big game such as Red Stag. Bullets vary from 154 grains to 227 grains and so the 8 x 60 mm rifle could be used for both long and short range work. Another popular bullet weight for the calibre was a 185 grainer. With a heavy bullet, such as a 227 grainer, the biggest antelope everywhere could be hunted for meat. The 8 x 60 mm saw use in the former Belgium colonies in Africa as well as in the RSA and the former SWA. Belgium and French hunters were not allowed to own 30-06 Spr rifles, as it was considered a military calibre, and hence the 8 x 60 mm was the closest rival. Sadly, about 5 years ago, RWS announced that they have discontinued their factory load, firing a 187 gr bullet at 2,810 fps, which is a very hot load in my opinion. However, I did still see some RWS ammo a year ago on Formalitos shelf. Handloads with a 200 gr Nosler Partition bullet will yield around 2,400 fps at safe pressure levels.

Another German design, was the 8 x 68 mm for long range work. With its bigger case, it could propel the heaviest 8 mm bullets at what was considered magnum velocities, way back then. The most popular bullet weight was a 224 gr soft point bullet - the standard factory load. I consider the stronger constructed 220 gr Swift A-Frame bullet to be the optimum for this calibre (2,700 fps). The 8 x 68 mm has the same powder capacity as the 300 H&H. The 8 x 68 mm was introduced in 1938 and it was setting the standards during those early years. However, it never gained a strong following in North America, for its elk and moose, or in Africa for Eland. Its main stronghold has been confined to Europe. The 8 x 68 mm was however popular with French and Spanish sportsmen, although relatively few were built up to WW2. In America though, the 300 Weatherby Magnum, introduced in 1948, provided stiff competition, whilst the 300 Win Mag became only available in 1963. Today the 8 x 68 mm calibre is declining in sales even though it is perhaps the most potent 8 mm calibre, shooting a 224 gr bullet. Ballistically, I would much rather prefer using a heavier bullet, than the other magnum calibres that mostly offer factory loaded ammo with 180 gr bullets. The neck of the 8 x 68 mm case is long in comparison with the 300 Win Mag, and is thus better able to hold a long bullet, such as a 224 grainer. 8 x 68 mm ammo has become scarce though, but it is still offered by RWS. The following load comes from a Rottweil reloading manual:

Min Load: 60 gr Rottweil R907 -- 224 gr RWS-KS bullet -- AOL 85.1 mm -- 2,477 fps
Max Load: 63 gr Rottweil R907 -- 224 gr RWS-KS bullet -- AOL 85.1 mm -- 2,625 fps

Remington introduced their 8 mm Rem magnum in 1977. It was based on the 375 H&Hs big case, just like the 300 H&H - 72.39 mm, about 4.4 mm longer than the German 8 x 68 mm. Strangely enough, it also did not become popular as its use was limited to the biggest North American game. Again, an excellent design. Only one proviso, like with all magnums, it should be used with strongly constructed bullets to prevent them blowing up on big and tough game. Poor bullets can ruin a calibres reputation ... we should never forget, the bullet is doing the killing and bullet performance is what counts ultimately. Initially, Remington offered 2 bullet weights - 185 grains and 220 grains, but the only factory ammunition offered today by Remington is a 200 gr Swift A-Frame bullet at 2,900 fps. It yields a fairly sharp recoil; more than the .300 Win Mag. Col. Craig Boddington, an American gun writer an avid hunter says .... "The 8 mm Remington Magnum has become one of my favorite hunting cartridges" - for elk, that is. Furthermore, he prefers handloading as he believes factory loads, i.e. 200 grain bullets, are not up to the calibres potential. What does he mean? ... Let me quote the man - "The Big Eight needs handloads with 220-grain bullets to reach its full potential". The message is very clear; increase your bullet weight. I love my 300 H&H, which also gives sterling performance with 200 and 220 grainers, but at somewhat lower velocities, as its case holds about 15% less powder. The 300 H&H became quite popular in South Africa and other former English African colonies, between its introduction in 1920 and 1963, when former British colonies became independent and the British had to leave.

A last thought ... of all the 8 mm calibres, the 8 x 68 is really the only one that promoted shooting the heaviest bullet, i.e. 224 grains, with a sectional density of .307.Most of the .300 Magnums came with 180 and 200 grain factory loads, with the exception of the 300 H&H, as Winchester used to offer a 220 gr load at 2,620 fps, but no more. I do believe that an eland needs a strongly constructed 220 grainer. I remember very well one day during 1977, when I was shooting on the bench with the late Willie Klotz, when he said to me that the 8 x 68 mm was for the connoisseur, and that it was quite unique in what it offers ... I was bedazzled, I did not quite understand and nor did he offer an explanation, perhaps because it was so obvious to him. Being a German gunsmith his whole life, he regarded himself as an expert in any event. What could the benefits possibly be over the 300 magnums?

* It is better suited to be built on a modified standard K98 action, as it has a shorter case than a 300 H&H or a 300 Weatherby Magnum.

* It yields lower pressure than the .300 Magnums, as the diameter is bigger and hence the expanded volume gets bigger as the bullet leaves the case when fired.

* It is a genuine Mauser design on a Mauser action.
* Some might consider its beltless case an advantage.

I would like to throw a stone in the bush now ... Did Winchesters .338 Win Mag, introduced in 1958, not perhaps occupy the US market for bullet weights between 225 and 250 grain, being the calibre of choice for long range big antelope, such as elk? A bit bigger bore than an 8 mm, but still a contender. Especially the 250 grainer in .338", with its good sectional density of .313, launched at 2,660 fps. However, the .338 Win Mag could not get itself entrenched in the SA market though, because of the arms embargo period (1979- 1994). It may change slowly now, but I think the 375 H&H has already captured that section of the market for bigger game and the fact that the .338 is not legal on buffalo.

Who will develop the next 8 mm calibre? Who is promoting the 8 mm today? Remington? I dont think so, as the one they have is good enough. Will Winchester perhaps go for a 8 mm after all the years during which they never had one? I doubt it. Will any European country? I dont think so, as the 8 x 68 mm is well designed. The 8 x 60 mm is history, as no manufacturer chambers for it anymore, but in my opinion, just as good as a 30-06 Spr. So, it looks like the 8 mm market has become stagnant. It has nothing to do with design. Existing rifles will be inherited by the next generation, who might use them or the youth might even have their own preferences. Once bullets and cases are becoming scarce, the end is near. I guess, sad circumstances killed the 8 mm and the present day mania of manufacturers to push lighter bullets faster as opposed to sacrifice some velocity for increased bullet weight. With scarcity of components and the high cost of imports, the most viable option seems to be the 300 H&H, if you have a need for a 220 grain bullet, but you will have to handload as all factory ammo only comes in 180 gr bullets. Also, no factory made rifles are offered anymore in 300 H&H - you have to get one custom built if you want a new one. We as hunters, must voice our opinions as to what we want. Most gun writers will write what their masters, who pay them, would like to hear. The new wave now is the short magnums by Winchester, which will most probably supercede the recent wave that Remington had with its ultra magnums, but sadly they too, by virtue of a short case neck and shoulder, cannot offer the hunter 220 gr loads.

John Pondoro Taylor already said in the 1930s that we had too many calibres, when he proposed that we only keep a bakers dozen (13). A tough call ... especially for today, with its unabated proliferation of calibres!