Can I get some info on these rounds?


I would like some info on the:

.215 Steyr
[color=#FF0000]Appears to be the same as the 5.45x39 with a .215 HS[/color]

.236 Remington Experimental
[color=#FF0000]Appears to be Remington’s chance at a 6mm military cartridge, based on the .30 Remington Rimmed[/color]

.25-100 Winchester Experimental

.256 Bang Experimental
[color=#FF0000]May be a necked .30-06 Springfield[/color]

.280 Roosevelt
[color=#FF0000]Charles Ross’ first attempt at a .280, and was a .30-03 case with a semi-rim and necked down. Lost in obscurity because of the .280 Ross, which could be considered as a development of the Roosevelt[/color]

.280 Westley Richards
[color=#FF0000]Might be a necked down .425 WR, is so, very similar to the .284 Achilles wildcat[/color]

.298 Westley Richards Miniature Express
[color=#FF0000]A British Rook cartridge, possibly a design leading up to the .300 Sherwood, or maybe an experimental development on that case[/color]

.30 Krag Rimless
[color=#FF0000]Also known as the .30 Blake or USA Rimless, designed as a rimless .30-40 for the Blake Rifle[/color]

.375/.303 Westley Richards
[color=#FF0000]A short lived cartridge, not a true .303, but a .330, was superseded by the .318 Rimless[/color]

.31-62 Winchester Experimental

.34 Winchester
[color=#FF0000]Originally the name for the .348 Winchester (Does anybody out there have a cartridge so headstamped, or was it just a name they were playing around with?)[/color]

6mm Smith and Wesson Experimental
[color=#FF0000]Appears to be another Smith and Wesson auto pistol experiment, akin to the .35 Smith and Wesson, which made it much farther[/color]

6.45mm Walther Ultra
[color=#FF0000]Used a .254 inch bullet and was introduced in the 1930s[/color]

7mm Steyr Experimental

7mm Browning Experimental
[color=#FF0000]Does appear to be the same as .28 Browning[/color]

8mm Walther Ultra
[color=#FF0000]Jonnyc, could you please post a pic?[/color]

.25 Eimer Colt
[color=#FF0000].25-25 Stevens shortened to 1.25 inches and loaded with an 86 grain bullet[/color]

.25 FBI Stinger

.28 Browning Experimental (Maybe the same as 7mm Browning?)
[color=#FF0000]Does appear to be the same as the 7mm Browning[/color]

.41 Winchester Experimental

.41 Smith and Wesson Experimental

.43 Eimer Colt
[color=#FF0000]A .30-06 case shortened to 1.34 inches and remed to take .429 bullets[/color]

.400 Kings Norton Experimental
[color=#FF0000]The .400 Kings Norton Rimless looks like a rimless .400 Nitro/Purdey[/color]

.425 Kangaroo
[color=#FF0000]Introduced in 1900 and marketed in Australia[/color]

.50 Kings Norton Experimental
[color=#FF0000]It appears to be a .500 Colt-Kynoch shortened and with the rim reduced[/color]

.500 Kings Norton Colt
[color=#FF0000]Same as above, just renamed[/color]

.52-70 Sharps
[color=#FF0000]A .50-70 Sharps cartridge with a slightly larger bullet for rifles with shot out barrels[/color]

.65 British Gatling

.65 US Gatling


Marry into a rich family.

I think some of those might not exist, like the 6.45 Ultra. I have an 8mm Ultra, so headstamped, and those are very scarce.


I looked up a few for you. Several are in past journals. If you are an IAA member, I suggest you buy the past issues CD. … AA-journal



Many of those are experimental, wildcats, or possibly non-existant. It would take considerable time (and research) to describe and/or furnish information on them. While most Forum members are more than willing to help, that’s asking for a lot. Research is a big part of collecting. You will learn a lot more by doing most of the heavy lifting yourself. Narrow that list down and I, and most others, will be happy to add whatever we know.

Sorry to sound like a old curmudgeon. Somebody had to say it.



On many of those, the extent of what is known is in Google results, or at least the Google results steer more clearly to a certain person in a forum who would know. Using quotation marks around any of those in a Gogle search will narrow it down nicely, like “.43 Eimer Colt”.


I have a 6.45 Geco or Ultra, so they do exist. Brandt & all, seemed to think it was not right or ? ? ? so stopped listing it. No idea behind if it’s right or wrong, but they do exist. In the last Brandt compilation of P&R cartridges there were several he did not continue to list that exist in collections, I can’t say who is right in this matter.


Hello ammocollectorME,
The information I have on the .25-100 Winchester Experimental is from Paul Fosters article “Winchester’s Forgotten Cartridges”, 1952
It is know as a long, rimmed, straight cases .25 caliber cartridge from the early 1900’s.
inches mm
Rim Diameter: 0.362 9.2
Base Diameter: 0.302 7.7
Neck Diameter: 0.283 7.2
Bullet Diameter: 0.257 6.5
Case Length: 2.215 56.3

All the best,


Hi All,
The information I have on the .256 Bang Experimental is:
The .256 Bang Rifle Experimental cartridge was developed for the Bang semi-automatic rifle. The rifle was developed by Soren S. Bang of Denmark. The rifle used the muzzle cone system of operation but found to be too light and complex to be adopted by the military.

Hogg, Ian V., Encyclopedia of Firearms, 1987

                inches	mm

Rim Diameter: 0.468 11.9
Base Diameter: 0.465 11.8
Shoulder Diameter: 0.429 10.9
Neck Diameter: 0.294 7.5
Bullet Diameter: 0.257 6.5
Case Length: 2.490 63.2

All the best,


Pete, in 1970 Hans Erlmeier, one of the author of the book, wrote: “After more research it appears that the so named ctg ‘6.45mm GECO’ never was made by the firm of Gustav Genschow. Most probably they are ‘wild cats’ made from a 7.65 Browning case with a 6.35 bullet. The cases were without headstamp.”

In 1974, he further said: "This cartridge has been withdrawn because it never existed. The only know specimen has been determined to be a fake”.

I can’t add anything else except for his opinion before withdrawing the round from the book.




Hi All,
The information I have on the .280 Westley Richards is that it was a necked, British sporting cartridge with a rebated rim.
The .280 Westley Richards seems to have been made from the .280 Ross case with the rim turned down to fit a standard Mauser bolt face. Cases have an ELEY 280 headstamp.

This is the .280 Ross case with the rim rebated to fit the standard bolt face ofthe Mauser action. Only Westley Richards is known to have made rifles for this special case, loaded with l60-grain bullet.

Hoyem, George, The History and Development of Small Arms Ammunition, Vol. 3, 1982

                inches	mm

Rim Diameter: 0.468 11.9
Base Diameter: 0.530 13.5
Shoulder Diameter: 0.421 10.7
Neck Diameter: 0.316 8.0
Bullet Diameter: 0.287 7.3
Case Length: 2.580 65.5

All the best,


Hello all (again),
Here is the information I have on the .31-62 Winchester also known as the .31-62-200 Winchester.
The .31-62 Winchester was developed for the Model 1886 Winchester rifle. This smokeless cartridge used a copper jacketed flat point bullet. There is a rifle in the Winchester Arms Collection in Cody, Wyoming. The rifle has a full length magazine and a rapid taper barrel with a lighter than normal forearm.

Hoyem, George, The History and Development of Small Arms Ammunition, Volume Four

                inches	mm

Rim Diameter: 0.605 15.4
Base Diameter: 0.577 14.7
Shoulder Diameter: 0.470 11.9
Neck Diameter: 0.362 9.2
Bullet Diameter: 0.328 8.3
Case Length: 2.102 53.4

All the best,


Hi all,
I have only a little information on the .41 Smith and Wesson Experimental and I have nothing on the .41 Winchester other than dimensions.
The .41 Smith and Wesson Experimental is not to be confused with the .41 S&W Magnum. This was an experimental cartridge developed by Smith & Wesson and loaded by Union Metallic Cartridge Company, but was never commercially introduced. The cartridges seen are loaded with self lubricating bullets.

.41 Smith & Wesson Experimental
inches mm
Rim Diameter: 0.456 11.6
Base Diameter: 0.407 10.3
Neck Diameter: 0.406 10.3
Bullet Diameter: 0.373 9.5
Case Length: 1.040 26.4

.41 Winchester
inches mm
Rim Diameter: 0.468 11.9
Base Diameter: 0.415 10.5
Neck Diameter: 0.411 10.4
Bullet Diameter: 0.400 10.2
Case Length: 1.290 32.8

All the best,


I have no idea whether a .215 Steyr exists.

A cartridge with a .215 headstamp and the dimensions of 5.45 x 39 is the .215 RWS.

Because at the collapse of East Germany no official data about the Soviet 5.45 M74 was available, RWS applied for a CIP homologation of a cartridge under this name. Otherwise it would not have been possible in the CIP countries to make 5.45 x 39 ammunition for the commercial market or sell weapons of that calibre. They just were proofed and marked .215 RWS.

Somewhat later the Russians had their original 5.45 x 39 cartridge accepted by CIP, and .215 RWS became forgotten, having fulfilled its purpose.


For .65 British Gatling see the page by Tony Edwards: … nd-gardner



Thanks Fede. For whatever it’s worth here are some photos. Lead cored bullet weight is 61.3 grains.
I got this from a resident of Ohio in the early 1980’s?, again for whatever that is worth.


Clark: This may seem like a quibble, but I feel it necessary to mention that Bang didn’t use “the muzzle cone system of operation,” but rather his own particular version of it. Later rifles using a muzzle cone, like the Walther G.41, have been referred to as “Bang system” when in fact they are not. Bang’s system involved a muzzle cone which moved forward, driven by gases following the bullet out of the muzzle, and operated the breech mechanism via a bellcrank and pullrod system. In the G.41 and a number of similar designs the muzzle cone was fixed and an annular piston within the muzzle cone assembly was driven rearward to activate an operating rod much like the Garand system. Jack


Hello Jack,
Thank you for the correction regarding Bangs design.
I know nothing about Bangs firearms.
Now I need to dig into them and learn more.
All the best,


Brian: Among arms writers in the last couple of decades confusing Bang’s design with other systems having a similar appearance at the front end has become more typical than not and it’s become, I’m afraid, one of my pet peeves. Julian Hatcher’s book called “Hatcher’s Notebook” has a pretty good illustration of how the Bang system works. Jack


Hello Jack,
I looked at “Hatchers Notebook”. Never thought to look there. It has a good explanation and diagram.
I understand that there were other rifles based on the Bang system as well.
Didn’t Maxim develop a similar system? Not the one he is famous for, but something similar to the Bang system?

As I looked at the diagram in “Hatchers Notebook” and Bangs Patent I can see where the confusion lays.
The patent drawing looks like a gas system pushing on a piston\connecting rod rearward.
See U.S. Patent 1,534,486, April 21, 1925, Self-Loading Firearm, Inventor Søren H. Bang of Copenhagen, Denmark

Thanks again for the discussion and information.


Brian: I wasn’t familiar with any interest by Maxim in gas operation, but Hatcher does mention that he held an 1885 patent for some form of Bang-like muzzle cone. That said, I’m not aware that he did anything with the idea. John Browning, on the other hand, converted a lever action Winchester to activation by a similar arrangement in the late 1880s. This was his first attempt at automatic design and eventually led to the gas system he employed successfully in the Colt “potato digger” machine gun. Jack