View Full Version : Webley Cylinder Conversions

April 11, 2012, 04:32 PM
People who know the Webley Mark series of caliber .455 revolvers know that guns in many of the later marks, especially, had their cylinders shortened to accommodate the US .45 ACP cartridge. My question is about the history of that conversion. Where did it happen: UK? Here? Both? Who did the conversions: Military? Importers? Dealers? I've never been clear about this; any info. welcome. Thanks.

April 11, 2012, 04:50 PM
I would be very surprised if anything less than 90% of such conversions were done by U.S. importers during the 1950s. Other than relatively limited use of Thompsons and 1911s, the Brits didn't use .45 ACP, so no reason for anyone on that side of the pond to do it. I don't think there was much of a distinction between "importer" and "dealer" in the days when handguns could be bought mailorder.
I have a S&W Hand Ejector .455 that's been fitted with a M1917 cylinder for a sort-of conversion to .45 ACP, and I'd be surprised if that wasn't done at the "local" level; could there have been enough extra or leftover cylinders to a lot of such conversions?

James K
April 11, 2012, 06:45 PM
There was (and is) a distinction between an importer and a dealer so far as licenses are concerned, but most importers also have dealer licenses.

As for those conversions, they were done after the guns were sold out of British government stores. Most were done in England, by Cogswell and Harrison, which at that time was owned by Sam Cummings, who also owned Interarmco (later Interarms). The cylinder was not shortened to allow use of .45 ACP ammunition, it was shortened to allow use of .45 ACP plus a half-moon clip, since the rimless .45 ACP will fall into the .455 Webley chamber without it.

The sole reason for the conversion was to allow buyers to fire those revolvers since there was no large stock of surplus .455 Webley revolver ammo. A British officer issued a Webley Mk VI would be given one (1) twelve-round box of ammo and told to get on with the war. One (1) more box per gun was kept in unit supply, presumably to be issued when the officer brought in 12 dead Germans.

There have been reports of those Webleys blowing with .45 ACP GI ammo; Webley fans have vehemently denied that any Webley could possibly blow, but the fact is that the working pressure of the .455 was on the order of 12-14k psi, while the .45 ACP runs 21k psi, meaning that for the converted revolvers, every .45 ACP round is a proof load. I strongly recommend not firing standard GI or equivalent .45 ACP loads in those guns.


Mike Irwin
April 11, 2012, 06:51 PM
Note, too, that Webley Mks I through III were chambered for black powder cartridges.

The Mk III had to be withdrawn from service upon adoption of cordite in 1892 because those guns couldn't even be trusted to stay together with the sedate smokeless loads that had been adopted.

April 12, 2012, 08:16 AM
Thanks for replies. So, I guess Interarms was the big player here, and the time, the early and mid fifties. Were there any other companies doing the same thing, specifically with Webley revolvers, does anybody know? Thanks again.

James K
April 12, 2012, 12:06 PM
There were a bunch of companies selling those converted revolvers, but most were buying them from Interarmco. I think Winfield may have been importing them and possibly having the work done here, but if so that was uncommon. English labor was cheap at that time, not to mention of high quality, so having work like that done in the States wouldn't pay.

The easy way to tell is to look at the proof marks. If they indicate .45ACP, then the work was done in England and the guns proved after conversion, as required by English law. (The law required that guns being sold out of government stores that had not been proven in a way acceptable under the law - which meant any U.S. guns - be proved before commercial sale or export. But if the guns were to be converted, the work could be done first, then the gun proved for the new cartridge.)


April 12, 2012, 08:12 PM
Note, too, that Webley Mks I through III were chambered for black powder cartridges.

The Mk III had to be withdrawn from service upon adoption of cordite in 1892 because those guns couldn't even be trusted to stay together with the sedate smokeless loads that had been adopted.

I would also add that the Mk. IV .455 was/is marginal at best for smokeless powder and should be handloaded with black powder or an acceptable substitute if one intends to fire it. The only Webley .455's that can handle a steady diet of today's smokeless powders are the Mk. V and Mk. VI and then only with loadings equivalent to the original .455 Mk. II loading.

Conversely, the Mk. III and Mk. IV .38 caliber revolvers can handle ammo loaded substantially warmer than commercial .38 S&W ammunition or what most manuals list as maximum for that cartridge. This is because factory ammo and load data for .38 S&W is kept intentionally mild out of deference to the weak U.S.-made top breaks that exist in large numbers in .38 S&W. The Webley/Enfield stirrup latch is much stronger than that found on most top-break revolvers and as such they can handle much stouter ammo. While I won't post the exact load data, I've run handloads with 200gr LRN bullets over a powder charge in excess of 50% over current book maximums with no ill-effect to my 1950's vintage Mk. IV (this load was very carefully worked up to and still not quite as high as what I've read others are doing with that particular powder for these revolvers).

April 13, 2012, 09:07 AM
Thanks very much. I think I have it on the conversions. I'm mainly interested in learning about my new-old 1914 Mark V, which is unconverted. It is covered with various military and proof marks, including several denoting (I think) proofing for modern powder: crown over BNP. I have ordered a box of Fiocchi .455 Mark II ammo (262 gr. bullet, box also says "GZN"). I'm hoping I'll be okay shooting this, which I have used without trouble in Mark VI's I've had over the years. I don't intend to shoot this much, but I would like to, now and then.

April 13, 2012, 12:52 PM
Your Mk. V should be just fine with Fiocchi or Hornady ammo so long as it hasn't been converted. If it has, you'll likely get light strikes since the cylinder won't have sufficient length to hold the case head against the recoil shield. If your revolver has been converted, your best bet to shoot it would be to hanload .45 ACP cases with moonclips or .45 Auto-Rim cases with .455 Mk. II loading data. A good bullet for handloading .455 Webley ammo is Remington's 255gr LRN. This bullet is reasonably close in weight to the original 262gr one and is of the proper .455" diameter. Also, the Remington bullet is plain swaged lead and can usually be found quite cheaply.

If you're handloading with .455 Webley cases, be aware that Fiocchi and Hornady brass use different size primers (one uses large pistol and the other uses small pistol but I don't remember which is which) so it would be best to either stick with one brand or the other or at the very least segregate the brass by brand.

April 13, 2012, 06:49 PM
Be aware that Fiocchi tends to load on the "hot" side with some of their specialty ammos.

April 13, 2012, 08:35 PM
Enjoy shooting your Webley, it's a nice piece of history. The Fiocchi stuff is great, I've run at least 400 rounds through mine in two years, no issues.