Webley 0.445in revolvers

I was reading Orbis “War Machine” article called “Pistols of the Great War” which stated that:
Still in service around the world,
Webley revolvers are arguably the
toughest and most accurate
handguns ever made. Their calibre
is 0.441 (1 1.2 mm) but, curiously,
they have always been referred to as
0.455 ( 1 I .6 mm). Below is the Mk I ,
introduced in 1887; above is the Mk 5
of 1913.
So, is it 0.441 or 0.445?

Not sure what the bullet measures out to exactly, but the round is universally recognized as the .455 Revolver cartridge.

Vlad, Maybe they are measuring the barrel at the lands instead of the grooves. Cheers, Bruce.

Vlad, the name of a cartridge is mostly only loosely connected with the actual bullet or barrel dimensions. The closer you look at it, the more complicated it gets.

“Calibre” is measured between the lands (for example .30 in = 7.62 mm). This is typically used for naming the cartridge (.30-06, or 7.62 x 51). Maximum bullet diameter today usually corresponds to groove diameter (in this case .308 in = 7.82 mm).

I wrote “typically”, because most 9 mm pistol calibres are actually not named after calibre, but after bullet diameter. The same applies to .455 Webley, or .308 Winchester. But the 9 mm Makarov does not fit in this mould: it is named after calibre; bullet diameter is 9.2 mm.

Another nicely confusing example is .38 Special which has a bullet diameter of only .355 in.

The basic rule is: there is no fixed rule. You have to look up actual dimensions in reloading manuals, CIP/SAAMI tables or the like.

Peelen - I may be wrong, but I believe the .355 bullet diameter you describe is that of the 9 mm Parabellum, and not the .38 Special. The .38 Special, and its big brother, the .357 Magnum, generally require a bullet of .357/.358 for good accuracy. Some Colts are exceptions - my own Python has a bore diameter of .356 but it shoots .357 or .358 jacketed and lead bullets with exceptional accuracy.

I agree that cartridge names are misleading. The .38-40 WCF is actually a .40 caliber cartridge - in fact, the first .40 S&W bullets used were nothing but jacketed versions of the common lead 180 grain flat point bullet designed for tube-loading rifles. The .30-30 Winchester is named, I am told, for being .30 caliber and case capacity of 30 grains of black powder, yet it was barely ever, if ever at all, factory loaded with black powder. The .32 Auto cartridge is closer to .30 caliber than it is to .32, and so on and on.

LOC6075, 8 Nov 1887 which introduced the Webley Mk I revolver into British service lists the calibre as .441" which is the bore size not groove size and of course it took the familiar .455" Webley Ctg.
This reference to .441" calibre has caused confusion to the point where some authours have claimed the Webley had its calibre changed later.
When the Lee Metford was introduced its Calibre was listed as .303" also its bore size.

John, you are right. I should have written .357 in.

Although I don’t regret buying it, I should have measured my 1925 Enfield Mk IV’s barrel and chamber throats first. The bore is a startling .449" max diameter and the chamber throats ran from .445 to .447.
After translating less-than-helpful disassembly instructions into actions, I removed the cylinder from the barrel group and easily drove a .451 round ball with surface oxidation down the bore from the forcing cone to the muzzle using a dowel. The oxidation was either compressed or stripped off clearly showing the lands and grooves of the rifling and measuring a max diameter of .449. Thinking that was way too small, afterward I drove a .452 SWC down the barrel – using much greater effort due to the increased bearing surface – only to get the same result: .449".
The chamber throats I measured with a caliper and double checked by trying to drop the now-.449 bullet through the throats. They measured from .445 to .447 and would not let the .449 bullet through with finger pressure.


Yes the chamber throat on Webleys is designed to be a tad smaller than the bore size.
This was a design feature to ensure the bullet was held firmly in the short case until the black powder burn reached pressure.
The bullets were designed with a deep hollow base which expanded by gas pressure to tightly fit into the bore/rifling as soon as the bullet was in the barrel.
I have owned many of these old Webleys and have fired thousands of rounds of both factory and reloads through them.

If you are going to reload for these the best results are only to be had with the correct hollow base bullets.

Jim Buchanan