.455 Webley Velocities?

[Bigslug]

Dealing with a mild case of "Wikipedia Fail" here.

Velocities for the standard 265 grain bullet weight range between 600 and 750 fps, but there isn't much in the references to the various cartridge models and marks saying where those differences lay. Cartridges of the World does nothing to clarify.

Anybody sitting on top of a more focused stack of source data?

[Outpost75]

Here is my test data:

.455 Velocity Data
_____________________________Velocity (fps), Sd __________Kirst Ctg. Conversion___”Rook Rifle”
____________________________Webley Mk VI 6” Bbl._____Ruger ROA 7-1/2”______H&R 20”
_____________________________Cylinder gap 0.018”_____Cylinder gap 0.004”____Solid Bbl.

Kynoch K42 Mk VIz 265-grain FMJ___537 fps, 29 Sd___________580 fps, 32 Sd________680 fps, 40 Sd

Handloads Assembled in Hornady .455 Mk II cases (0.77”) with Winchester LP primers

#452374 225-gr. LRN 5.0 Unique____648 fps, 24 Sd___________716 fps, 11 Sd_______814 fps, 14 Sd
MiHec 265-gr. Mk I 4.5 Unique______538 fps, 24 Sd___________679 fps, 32 Sd_______788 fps, 11 Sd
Accurate 45-259H 3.5 Bullseye______622 fps, 6 Sd____________720 fps. 16 Sd_______813 fps, 18 Sd

Handload in Starline .45 Schofield Case modified to .455 Mk I (0.87”) by Reed’s Custom Ammo

Accurate 45-259H 3.5 Bullseye______546 fps, 16 Sd___________641 fps, 9 Sd________753 fps, 11 Sd

Column Means By Gun____________Webley 0.018” gap______Ruger 0.004” gap____20-inch rifle
Pooled Avg. All Samples:___________578 fps________________667 fps______________770 fps
Velocity Gain Over Webley__________0____________________+89 fps______________+192 fps

Cylinder throats of all original Webley revolvers I have measured were tighter than barrel groove diameter, typically .449-.451." Colts and S&Ws, usually have very large cylinder throats of .457-.459” with barrel groove diameters being .455-.457”.

Forcing oversized bullets into tight cylinder throats increases chamber pressure dangerously, PARTICULARLY when bullets are full metal jacketed or cast hard! Safe results require SOFT lead bullets not exceeding 10 BHN, sized to fit the cylinder throats. Bullet weights from 230-270 grains are recommended to shoot to point of aim with fixed sights. I recommend that ammunition destined for “shaved” .45 ACP revolvers be assembled into .45 Auto-Rim cases for positive identification.

Loads developed in stronger Colt and S&W .455 revolvers using larger bullet diameters and producing velocities over 700 fps should NOT be fired in any Webley revolvers!

Limit revolver velocity of 270-grain bullets to 600 fps and 230 grain ones to 700 fps by using 3.0-3.5 grains of Bullseye or 4.5-5.0 grains of Unique. You can determine safe charges with other powders in “shaved” .45 ACP Webleys or unaltered .455 revolvers using the 0.88” length .455 Colt cases by adhering to the “start” load charges listed for .45 ACP using #452374 in the Lyman Cast Bullet Handbook, 4th Edition (2010) on p.278, which do not exceed 13,000 cup.

Reduce these charges by 10% either for heavier bullets or for use in shorter 0.76” Mk II cases, unless you are able to measure velocity of your revolver over a chronograph. Careful charge adjustment may be cautiously used to obtain uniform ballistics within the stated limits to compensate for a very large cylinder gap over 0.010”, which is very common in these revolvers.

Hope this is helpful.

210263210264210265

[Bigslug]

Well, that will indeed be handy, as my next batch is likely to be stoked with Bullseye.

But I'm hoping that someone has the "official" specs to go with the British "mark" designations. Not so much worried about blowing up a gun as what was being fired at the various points in the timeline.

. . .and your post does bring up another ponderance: what barrel length were they spec'ing their speeds in? . . .and were they even concerned with FPS numbers (as opposed to "this charge works") at various points?

[curator]

Outpost75:

Thanks for the useful data on Webley revolvers. As the recipient of my grandfather's MkIV .455 Webley, I have been reluctant to stoke the pressure up to .45ACP range. Unfortunately, he had the cylinder "shaved" by a machinist friend of his once Dominion no longer made the .455 Webley ammo available in Canada. I have reloaded .45 Auto-rim to about 650 fps using the Lee .454-255RF boolit and Unique. I will have to check on the cylinder throats diameters to see if they are sizing down the boolits before they enter the bore.

[Outpost75]

... I'm hoping that someone has the "official" specs to go with the British "mark" designations...
what barrel length were they spec'ing their speeds in? . . .and were they even concerned with FPS numbers (as opposed to "this charge works") at various points?

The closest thing I have to an original source is my copy of the Text Book of Small Arms (1929), which on p.263 describes .455 revolver ammunition in Section 8.

There is no indication of the test barrel length, or whether the velocity test is taken from a revolver, or from a solid barrel. Not much help. A few of of the pertinent sections quoted below:

"Only a low standard of accuracy is obtained, and a figure of merit of four inches at a range of fifty yards is considered satisfactory. The velocity obtained is about 580 feet per second, but a variation of 30 feet above or below this is permitted and no limit is placed on the mean deviation from the average velocity."

Nothing stated as to type of test barrel, number of shots fired, number of groups...

Related to pressure tests:

"Copper crushers compressed to 4-1/2 tons are used and the mean pressure should not exceed 5-1/2 tons, while no single round should give a pressure exceeding six tons."

Pressure tests in British Army practice at the time used the base-crusher system, in which an oiled case was driven back in the chamber of the pressure test barrel to measure the backthrust of the case head against the breech face. Results will vary based on the case head diameter which the powder gases are able to work against, to the compression of the copper does not correspond to psi, but tons compression of the copper under the test conditions.

Without reference to the actual cartridge specification, I can only presume that the test methods and procedures followed the common industrial practice at the time.

A summary of the different marks of revolver ammunition from the Cast Bullet Association's Fouling Shot, provides some additional general information:

Six main types of .455 ammunition were produced:

The .455 Webley Mk I had a case length of 0.88” and was introduced in 1891. It was loaded with a 265 grain lead, hollow-based, round-nosed bullet of 1:12 tin/lead, and 18 grains of black powder, lubricated with beeswax. A few experimental Mk I cordite cartridges were produced before the Mk II. The longer Mk I case was used for sporting, Boxer-primed, smokeless loads by CIL until the early 1970s.

Starting with the Mk ll, introduced in 1897, subsequent .455 British service cartridges were loaded in the 0.76” case.
This was intended to reduce excessive airspace to improve ballistic uniformity with smokeless powder. The Mk II 265 grain lead, round-nosed, hollow-based bullet resembled the nose shape of the Mk I, but had a shallower hollow base, reducing the bullet’s overall length to improve gyroscopic stability and larger lubricating grooves. Its 6.5 grains of Mk I chopped Cordite produced 600 fps from a 6-inch barrel. (not stated whether revolver or solid test barrel).

The Mk III cartridge, introduced in 1898, was the famous "Manstopper" bullet. It was intended for police, civilian defense, and colonial use and was a double-ended, 218-grain design, swaged of 1:12 tin/lead, having hemispherical cavities at each end—one to seal the barrel, the other to deform upon impact. It was loaded with 6.5 grains of chopped Cordite for 600 fps. Because it was not compliant with the Hague Convention of 1899, the Mk III was withdrawn in 1900 and the Mk II cartridge was reintroduced.

The Webley Mk IV, introduced in 1912, featured a solid, 220 grain, flat-nosed, hollow-based wadcutter. It was loaded with cordite propellant, producing 600 fps, its design objective intending to be more effective than the round-nosed Mark II, but without violating the terms of the Hague Convention.

The Mk V, introduced in 1914, was identical to the Mk IV, but formed from antimonial-lead-alloy recovered from salvaged storage battery plates. This wartime manufacturing expedient, was intended to conserve tin as a critical wartime material. It was in use only from April through November 1914. Harder antimonial-lead bullets proved less than completely satisfactory, due to barrel leading. The Mk V was almost immediately withdrawn and the Mark II returned to service. Remaining Mk V cartridges were used up for training and target practice and remaining in-process Mk V marked cases were assembled with Mk II bullets.

The Mk VI cartridge, introduced in 1939, is the variant most commonly found, used during WW2. It has a 265-grain FMJ, hollow-based Hague-compliant bullet propelled either by 5.5–7.5 grains of chopped cordite, or alternately 5.5-6.0 grains of flake nitrocellulose, the powder charge being determined at the time of loading to produce 625 +/-25 fps. Cordite-loaded cartridges bore a "VI" in the head stamp, whereas nitrocellulose-loaded cartridges were marked "VIz".

Although obsolescent by the end of WW2, the Mark VI cartridge continued to be made into the late 1960s by Kynoch to fill export contracts for Pakistan, Kenya and other export customers. Late production was produced with small size Berdan primers. Remington and Winchester produced .455 in both case lengths prior to WW2. CIL in Canada loaded .455 Colts into the 1970s. Hornady produced a limited run of Mk II ammo in 2008. Fiocchi is the only current occasional producer of .455 Mk II cartridges, other than custom loaders.

[Bigslug]

That thar is what I was after! Thank you!

Some telling info there, relevant to some of our earlier discussions of these guns. If the CBA article is correct that the design of the MKII bullet was in fact to make it more stable, that would seem to indicate that the MKI was running the ragged edge of tumbling, which at a pokey 550-610 fps seems pretty likely. My own initial batches of rounds with MKII headed more for the 700 range, and they're pretty stable in punching through a long string of milk jugs. Dialed down to under 600, one thinks they might not have enough spin to prevent a nose-over on impact. Now that I've got what is presumably the proper recipe, I might just have to bug a contact in the industry that does gelatin shoots. I've seen military 5.56 yaw in the stuff - it would be nice to put that aspect of the round to bed. Given that Thompson and LaGarde said it did better in livestock testing than the .45 Colt (kind of a mind-bender, that), you have to think either "fluke" or "strange dynamics".

Kinda makes me wanna drum up a group buy for the MKI to see if there's anything to that.

[Outpost75]

That thar is what I was after! Thank you!...If the CBA article is correct that the design of the MKII bullet was in fact to make it more stable, that would seem to indicate that the MKI was running the ragged edge of tumbling... . My own initial batches of rounds with MKII headed more for the 700 range, and they're pretty stable in punching through a long string of milk jugs. Dialed down to under 600, one thinks they might not have enough spin to prevent a nose-over on impact...- it would be nice to put that aspect of the round to bed. Given that Thompson and LaGarde said it did better in livestock testing than the .45 Colt (kind of a mind-bender, that), you have to think either "fluke" or "strange dynamics". Kinda makes me wanna drum up a group buy for the MKI to see if there's anything to that.

A friend has a MkI mold made in UK which DOES tumble reliably at 550 fps, but accuracy beyond across the bar distances is poor compared to the MkII, he says.

This 100-yd. target fired with my MkVI giving full front sight Kentucky Elevation is typical, ten hits out of 12 on full-sized IPSC silhouette, whereas my .44-40 Ruger is good for head shots.

210307

[Outpost75]

Outpost75:

Thanks for the useful data on Webley revolvers. As the recipient of my grandfather's MkIV .455 Webley, I have been reluctant to stoke the pressure up to .45ACP range. Unfortunately, he had the cylinder "shaved" by a machinist friend of his once Dominion no longer made the .455 Webley ammo available in Canada. I have reloaded .45 Auto-rim to about 650 fps using the Lee .454-255RF boolit and Unique. I will have to check on the cylinder throats diameters to see if they are sizing down the boolits before they enter the bore.

Both my Boer War era MkIV and my 1914 MkVI had tight cylinder throats and shot much better after the throats were uniformed.

The MKIV was done with a Manson .452" mouth reamer of the same type commonly used to do Rugers.

The MkVI would not clean up with the .452 reamer, due to pitting, so I had DougGuy uniform and hone the chambers to .455" and accuracy was also much improved.

The soft, hollowbased Mk.II bullet was intended to squeeze into tighter cylinder throats to boost pressure to get a more complete burn of a small powder charge, then the hollow base would upset to seal the grooves as the bullet transitioned from the cylinder to forcing cone and barrel. While suitable for very soft bullets and black powder, this is a recipe for blowing cylinders if attempted with hard, oversized bullets and fast-burning smokeless powders.

Having cylinder throats uniformed to barrel groove diameter or up to +0.0015" larger improves both accuracy and safety. After cylinder throats were honed I sold my MiHec MkII mold and now have standardized on the "Modern Webley Bullets" from Accurate. Of course, when you order, you can specify alloy and desired as-cast diameter. Given normal tolerance being positive, specify .454 bands as minimum, if you want .455 bullets. The "nose tolerance negative" note, eases fast reloading with speed loaders so that rounds are not a forced-fit into cylinder throats.

210310210311210312

I had the 45-245D mold modified to resemble the Manstopper cup point, but with solid base, weighing 230 grains in 1:40 tin-lead, by Erik Ohlen at www.hollowpointmold.com

210316

[Bigslug]

My 1917 MKVI has the same throats-smaller-than-bore issue, and I gave some thought to opening them up, but ultimately decided that the entire purpose of breaking out a Webley is to immerse oneself in archaic practices. Since I've got a steady supply of shotgun slugs (40-1) and jacketed scrap (30-1) coming in, finding soft stuff is not a problem.

Really looking forward to the conclusion of the MP group buy for the MKIV slug. That should slake my desire for a little more whupass out of this thing. . . but yeah. . .wanna see if I can get a MKII to swap ends.

[Bigslug]

Well. . .I'm glad Outpost gave the .38 S&W thread a bump to the top. Looks like I already backed the velocity down with Bullseye and 40-1, and no, it didn't tumble.

Too many projects, going senile, or both.:veryconfu

[17nut]

WC Dowell - The Webley Story:

210599
210600
210601
210602

So anything from 580fps to 700fps is official!

[Bigslug]

17nut: Thank you! Copied and saved.

Outpost: It tickles me greatly that you're shooting .455 Webley out of a rifle. That's got to be addictive. It ain't always about the biggest bang.

[Outpost75]

Outpost: It tickles me greatly that you're shooting .455 Webley out of a rifle. That's got to be addictive. It ain't always about the biggest bang.

John Taylor is a creative gunsmith and clever mechanic. Chamber was roughed with .38-40 reamer, to cut the rim seat and the .456 shoulder diameter and 6-1/2 degree shoulder angle cut the ball seat and throat, whereas the .38-40 neck doesn't cut in the .45 barrel, which was a Green Mountain .45 ACP "Gunsmith Special". Chamber body cut with .45 ACP reamer, which also provides stop surface for mouth of .45 ACP case. John's rimless extractor drops down when action is open so extractor hook clears circumference of case body so .45 ACPs drop right in. As action is closed extractor hook engages rim so ejection is positive when action opened. While .455 rim is thinner than depth of .38-40 rim seat, extractor hook provides positive headspace and reliable ignition and ejection. Rifle will shoot either .45 ACP or .455 Webley accurately, also accepts shot loads assembled in Starline 5 in 1 blank cases.

Most fun gun I own!

210678210683

[LIMPINGJ]

Outpost75 what model is the XS sight you have on that barrel, also did you send that sight to John or did he provide it when he did the barrel? I have a Yildiz 410 I am getting ready to send John to get a 32 S&W Long barrel and need to decide on a rear sight.
Thanks

[Outpost75]

Outpost75 what model is the XS sight you have on that barrel, also did you send that sight to John or did he provide it when he did the barrel? I have a Yildiz 410 I am getting ready to send John to get a 32 S&W Long barrel and need to decide on a rear sight.
Thanks

John got the XS sight and modified one to fit into a 3/8 dovetail. Makes a very nice install.

On another gun for me he took a US M14 front sight with ears and cut off the bottom, shaping it into a standard 3/8" dovetail so that I could have a sturdy front sight with protecting ears 0.4" high.

Clever guy.