Identiffy .455 Cartridge

Hello, I have a Webley Mark VI 1918 revolver. I have acquired some ammo with K43 VIZ stamped on them. Is this .455 suitable for use is this revolver or is it for an auto loader? Is it manufactured by Kynoch ? Any info you can give will be much appreciated.

George W Patten
Nickname General George

Yes, that is .455 revolver ammunition but it dates from WW2, manufactured by Kynoch in 1943.

Your revolver would have used the .455 Mark II cartridge with a plain unjacketed lead bullet, a subject the Germans complained about frequently.

Just prior to WW2 the British dcided to adopt a jacketed version which became the MarkVI cartridge. The “z” indicates it is loded with NC powder and not cordite. The ballistics are virtually identical.


Yes, you can use .455 Mark VIZ in your Webley Mark VI revolver. It is nice you have one of these good old revolvers in its original caliber, which I am sure you have verified (?). Hundreds of these revolvers entered the U.S. market at a time when there was little ammo available for them - basically only Dominion Brand commercial ammunition, expensive for the time. Gunsmiths started shaving the back of the cylinder off to accept the .45 ACP cartridge in half-moon clips. This worked o.k. and made saleable (average price when these came in was, as I recall, between ten and twenty bucks, hardly worth the time and effort for a dealer to do the paper work to sell them, at least in a state like California). However, the conversion made them unsafe to shoot with the original caliber due to the huge increase in headspace caused by the conversion.

Today, one in the original caliber and nice condition (of course, they did not generally bother with the conversion of poorer-condition Webleys as it was not economically feasible, the price of the conversion being as much as a poor condition Webley was worth) is hard to find, and value higher than a new, good quality, commercial revolver.

As I recall, the Webley .455 Auto Pistol, which has its own rimless version of the cartridge, had a circular recess at the rear of the barrel so that they could be single-loaded with .455 Revolver ammo in an emergency, although the pistol became a single-shot, as you could not use the revolver round through the magazine. At Least, the military Mark I and Mark IN (essentially the same pistol) had this, as I recall.

Thank you gentlemen. The information is appreciated.


TonyE, are you sure my ancestors complained about lead bullets? They had the M83 revolver still in inventory at the beginning of WWI, also using a lead bullet, of course. I would have to look it up but would not be surprised if even M71/84 rifles were used by garrison units and the like.
As far as I know, the .303 Mk VII was what they complained about (tip breaking off easily in what we today call intermediate barriers).

While we are on the subject of the Webley Mark VI and its ammunition; I have a question. I have a Webley Mark VI and several vintage cartridges. I have “test fitted” several of my .455 cartridge bullets into the end of the barrel to see how these bullets engage the riflings. All of them slide completely into the barrel and stop at the cartridge case. Only modern made Fiocchi .455 bullets barely “caught” the riflings at the end of the barrel. Maybe the bore is worn but it is shiny pristine looking. The pistol fires OK, but I could not really get a very good shot group. Is the normal for this pistol? The pistol has not been modified for .45 ACP. The only thing I could think was maybe because of the sharp taper of the bullet, the part of the bullet in the case is where it finally engages the riflings after firing?

Hi George,
Yes this apparent “loose fit” is normal for these revolvers. the soft lead bullets had a deep hollow base that expanded into the rifling when fired. I once read the technical reason for this, but my poor old memory has let me down again.
I once owned a number of these Webleys in all the calibres and different marks and before they were banned over here I used to shoot them in completion at Bisley. I once bought a large qyty of the circa WW2 ammo you mention but a lot of it failed to fire. possibly badly stored ?

The .455 has quirky dimensions for which I can offer only sketchy explaination. The designated powder charge was pathetically small and relied on an undersize ‘leed’ in the chamber to apparently act as a restriction to build pressure. The bullet then relied on a flaired skirt to engage the rifling. Remember it was designed as a BP load originally.
We used to ream the cylinders to bore size and then massively overload them with fast burning powders such as “B” and actual size bullets. The pistols were transformed!