BL 6 inch 26 cwt Howitzer

[Starlight]

Hi,

Can anyone tell me the shells that were used in WW1 for this howitzer and the dates when the 86 lb and 100 lb streamlined shells were first used?

Thanks

Steve

[Old Tom]

Hello,

Not much detail I'm afraid, my notes on this how are :

BL 6” 26 cwt How Mk1 – late 1915 – redesign of 30 cwt – box trail, better recoil and breech – 3 cwt heavier 3 ton 12 cwt – 695 made by end 1915, 3633 by end of war and 713 relined and reissued. – hydro pneumatic variable – shrapnel 100 lb 11,400 yds with 86 lb shell, 9,500 with 100 lb, 1409 f/s with 86 lb shell . Last used 1941, Recoil system used on 4.5" and 5.5" in WW2.

I assume that the 'stream lined' rounds were the only ones, but don't recall a mention of them.

Information from,

British Artillery Weapons and Ammunition 1914-1918 I.V.Hogg and L.F.Thurston

Old Tom

[johnreed]

Steve

As in the previous post I concur, and I also cannot find any mention of the streamlined shell, I presume you mean the Boat Tail design. If you can hold out until I go to the James Clavell Library I will get any information I can and will contact you. I will be going in the next fortnight.

John

[Starlight]

Thanks for the quick responses. In searching for details on the 6 inch howitzer over the past few weeks I found that the original 30 cwt gun fired a 118.5 lb shell 5,200 yards and that the specs for the redesigned 26 cwt version asked for a 100 lb shell with an effective range of 9,500 yards. As far as I can tell from the information I have, the 86 lb and 100 lb shells that were later used were in fact the streamlined shells but I wasn’t sure when they came into use, at the time the 26 cwt version was introduced or later, perhaps after the War. From the details you have given me ‘Old Tom’, it looks like they were the standard ammunition for the 26 cwt version right from the outset. If you can confirm this John when you go to the James Clavell libray, I would be most grateful.

Thanks

Steve

[ororkep]

Steve,

The term light was first applied to the 100 lb Shell BL HE 6 in Howitzer. These shells were designated ‘light’ from the outset of production of the 26 cwt How, although they could be used with both 30cwt and 26 cwt howitzers. It only weighed 100 lb when fitted with the actual fuze, which distinguished it from the earlier 120 lb shell (actual 118.5 lb) provided for use with the 30 cwt model. Fuzes 100, 101, or 102 fitted with delay, or No’s 44 or 106 could be used with it, and 101 E when required for a crater effect. The shells were specially stamped on the base ‘6-in How BL’ to prevent use with similar calibre guns, as the shell walls were not thick enough to withstand gun pressure on firing. The longer-range even more lightweight 86 lb shell only came into use from November 1918, too late to see service in WW1.

Source: Siege Howitzer 2nd edition ammunition handbook 1917.

Regards Paul

[Starlight]

Thank you Paul, that's exactly what I wanted to find out - that the only shell used in the 26cwt 6 inch howitzer during the Great War was the 100 lb shell that you described in detail.

Regards

Steve

[Starlight]

One last question Paul. Can you tell me the muzzle velocity and range of the 100 lb shell and were different charges used to vary these?

Regards

Steve

[cahoehler]

Steve

A belated reply on the 86lb streamline shell

On page 206 of Hogg WW1 there is a very interesting pic of a 6in 26cwt Mark 1C (streamline) projectile with a shell length of 21.34in (23.825in OA) and the 106E fuse - could this be the elusive 86lb shell of 1918? This same pic is on page 247 of Hogg WW2 (the 100lb Mark 1D with a shell length of 23.86in and using the 117 / 119 'streamline' fuze is on page 251).

A later even more streamlined Mark 1D with the ‘streamline’ 117 Fuze is shown in figure 5.24(g) of the 1936 Text Book on Ammunition

The still later Mark 2D is shown on Nigel F Evans WW2 site http://members.tripod.com/~nigelef/directory.htm.

The range of 11400 yards often quoted for the 86lb shell came from the 1934 Range Tables and was for the Mark 2D (streamline) shell.

Fig 5.24 (e) of the 1936 Text Book of Ammunition shows an interesting comparison of the 18-pdr Mark VII with the 106E Fuze and the 18-pdr Mark I C (Streamline) with the ‘streamline’ 117 Fuze.

The shape of the head of the shell is given by the crh (caliber radius head). The original 100lb shell had a simple 2 crh while the Mark 2D 86lb shell had a complex 5 / 10 crh. The codes for shape are given below

Caliber Radius Head Groups

Mark I Under 2

Mark I A Over 2 Up to 4

Mark I B Over 4 Up to 6

Mark I C Over 6 Up to 8

Mark I D Over 8 Up to 10

1. Hogg, I V and Thurston, L F , British Artillery Weapons and Ammunition 1914-1918, (London 1972).

2. Hogg, I V , Twentieth-Century Artillery, (Hoo 2000)

3. Hogg, I V , British & American Artillery of World War Two, (London 2002)

4. Hogg, I V , Allied Artillery of World War One (Marlborough 2003)

The cartridges for the 6in 26cwt to follow.

Carl Hoehler

[cahoehler]

Steve

The cartridges and the muzzle velocities as promised

The initial cartridge for the 6in 26cwt was filled with about 4 ¾ lb of Cordite MD (Modified) Size 8 (from the diameter (0.08in) of the extrusion die) and was built up from a mushroom shaped core and stalk surrounded by 2 segments. This was a seemingly labour intensive construction with the “stalk” made up from about a 1 ½ in bundle of 10 ½ in long cordite sticks surrounded by a “head” of 3 ½ in long cordite sticks in a shalloon (‘A lightweight wool or worsted twill fabric’) bag. The 2 segments also in shalloon bags, shaped to fit around the “stalk”, were of 7 ½ in long cordite sticks. This design exploited the advantages of cordite while still allowing the weight of the charge to be readily reduced. The nominal weight was later corrected to 4lb 11 ½ oz. In 1917 the cordite would be replaced by up to 5 ¾ lbs of American NCT (Nitrocellulose Tubular) which was hygroscopic and required special packing.

4lb 14oz cordite MD see pic above

Section 1 2lb 12.5oz 850 f / s

Section 2 0lb 11.75oz 1000 f / s

Section 3 1lb 5.75oz 1240 f / s

Charge weight 4.875 lb

5lb 14.5oz NCT (Sizes 7 & 22) see pic above

Section 1 2lb 1.5oz 707 f / s

Section 2 1lb 0.5oz 850 f / s

Section 3 0lb 13.25oz 1000 f / s

Section 4 1lb 15.25oz 1240 f / s

Charge weight 5.906 lb

5lb 14.5oz NCT (Size 16) essentially the same as above pic

Section 1 2lb 3.75oz 707 f / s

Section 2 1lb 0.75oz 850 f / s

Section 3 0lb 13.5oz 1000 f / s

Section 4 1lb 10oz 1240 f / s

Charge augmenting 0lb 6oz

Charge weight 6.281 lb

The NCT cartridges were sized to match the muzzle velocities of the original cordite cartridge. Sections 1 + 2 giving a muzzle velocity of 850 f / s. Section 1 would give a new minimum velocity of 707 f / s (sic). A 6oz “Charge Augmenting" was later issued separately to “obtain a small increase of Range”. The 1936 Text Book of Ammunition talks of a monobloc "super charge" in the Great War.

The NCT was a single-base ‘granular’ solid propellant (ie not tubular or any of the other many shapes that were used later) much like modern rifle propellants and required about a 10% to 15% increase in weight for the same velocities as the hotter and ‘stronger’ double-base cordite MD. The size of NCT is also given by the diameter of the extrusion die in hundreds of an inch.

My deepest thanks go to ororkep and Mike_H for supplying all of the scarce information

1. H M S O, Treatise on Ammunition 10th Edition (London 1915)

2. H M S O, Handbook of the B.L. 6-inch, 26-cwt, Howitzer on Travelling Carriage (Land Service) (London 1916)

3. H M S O, Notes on the ammunition for siege howitzers / Ordnance College. (London 1917)

4. H M S O, Text Book of Ammunition 1926 (London 1926)

5. H M S O, Text Book of Ammunition 1936 (London 1936)

6. Union of South Africa, Text Book of Ammunition South Africa 1945 (Pretoria 1945)

Carl Hoehler

[Starlight]

Hi Carl,

Thank you so much for taking the time and providing me with such a detailed response - exactly what I wanted!

Regards

Steve

[cahoehler]

Guys

frans (De Diggers at Boezinghe) has very kindly helped me to upload previously lost and yet to be uploaded pix.

4lb 14oz cordite MD

http://farm1.static.flickr.com/213/4847835...g

5lb 14.5oz NCT (Sizes 7 & 22 composite)

http://farm1.static.flickr.com/181/4847835...g

Caliber Radius Head

http://farm1.static.flickr.com/210/4847835...g

Carl Hoehler

[cahoehler]

Guys

Some more

6-inch 30cwt howitzer cartridge

http://farm1.static.flickr.com/192/4847835...g

Mark VII and Mark IC (Stream line) 18-pdr projectiles

http://farm1.static.flickr.com/221/484783508_3e0e8364c0.jpg

6-inch howitzer Mark IC (Stream line)

http://farm1.static.flickr.com/187/4847835...ff6abb943_b.jpg

Carl Hoehler

Guys

The last pic is of course the Mark ID

Carl Hoehler

[Guest]

I'd like to 'bump' an old topic if I may. I've been reading the war diary of my great-grandfather's battery, 180 Siege Battery RGA. In terms of the shells being fired, there are references to the number of rounds being fired without specific reference to the type. Occasionally, however, there are references to RX, which appears to be used against trenches, and LX , which seems to be used to target dugouts. Does anybody know what these are?

 

An example is below- date (26/09/2017), time of day and location suggest this is during the battle of Paschendaele. Thanks.

 

Edited 16 March , 2018 by Guest

[kevinrowlinson]

At that time 180 SB was a 4 x Hows. battery. This was split into 2 sections of 2 x Hows.

RX indicates right (hand) section (2 Hows)

LX indicates left (hand) section (2 Hows)

 

Kevin

[Guest]

Thanks Kevin, the diary now makes a lot more sense.