WW1 Grenades both British and Enemy.

[Lancashire Fusilier]

I am pleased to share a very interesting item from my Collection, a WW1 Mills No.23 Mk.II Hand Grenade made during the middle part of WW1 at the munitions factory of Dobson and Barlow, in Bolton, Lancashire.


Following the outbreak of WW1, the British Army saw an immediate need for a munition which would give a single soldier the firepower to dislodge an entrenched enemy by arming an explosive and throwing/lobbing it in the enemy's direction, and the resulting explosion and shower of metal fragments would kill, maim or shock the enemy.
The War Department asked William Mills of Birmingham ( 1856 - 1932 ) to look at designing and manufacturing a hand thrown grenade. Mills the son of a Sunderland shipbuilder, who had spent a period of time at sea following a apprenticeship as a marine engineer, was an enthusiastic inventor, who had established a notable reputation as a Metallurgist having built the first aluminium foundry in Britain and had also become well known for the design and manufacture of golf clubs.
His design for a metal cased, cast iron hand thrown grenade was approved, and in May 1915 became the Mills Grenade No. 5 Mk.I with the Mills Grenade remaining the dominant hand grenade throughout WW1, with over 75 million Mills Grenades being manufactured by Mills and other manufacturers. In 1922 William Mills was knighted for his invention and service during WW1.
Weighing 1.69 lbs., the pineapple shaped cast iron case, bulbous in the middle, fitted well into the thrower's hand. The casing was serrated so that upon detonation it broke into many fragments, thus becoming a fragmentation grenade.
Through a filler-hole at the top of the grenade, the grenade body was filled with the high explosive Baratol, which was made up of TNT, barium nitrate and wax. Once filled, the filler hole threaded plug was secured in place.
Through the base hole, the internal parts ( see attached diagram ), consisting of the Detonator, Percussion Cap, Time Delay Fuse, Striker Spring, and Striker, all of which were housed in the Centre Tube, were inserted, and the threaded base cap was secured in place.
In the ' safe ' position, the Striker was held in place by the Striker Lever, which in turn, was retained in position by the Safety Pin.
To arm the grenade the thrower would pull out and remove the Safety Pin, and at the same time keeping their hand firmly on the Striker Lever so as to retain the Striker in the loaded position.
When released from the thrower's hand and thrown/lobbed at the enemy, the Striker Lever ejects and flys off, releasing the sprung Striker which fires down hitting the Percussion Cap thereby igniting the time delay fuse which detonates the Detonator and explodes the High Explosive inside the grenade.
Originally, the Time Delay Fuse was set at 7 seconds, which proved to be too long, giving the enemy time to shelter or take cover, or even throw back the grenade, so this delay was eventually reduced to a 4 second delay.
The blast field from the Mills bomb/grenade was some 100 feet, so extreme care needed to be taken in the use of the hand grenade.
The grenade was stored and transported in boxes of 12 grenades, with the Detonators being carried separately in a Detonator Tin carrying 12 Detonators housed in a round wooden block, with assembly taking place just prior to combat.
The armed grenades were originally carried in canvas buckets, holding 24 grenades.
Later, Bombers in Bombing Parties carried the armed grenades in a canvas vest with individual pockets for each grenade.
The British bombing party/team usually consisted of nine men, an NCO, two throwers, two carriers. two bayonet-men to defend the team, and two ' spare ' men in case of team casualties.
As the bombing party reached the enemy trench, the grenadiers/bombers would race down the trench throwing grenades into each dugout they passed, killing the occupants.
One of the greatest ' grenade ' battles of WW1 occurred on the Pozieres Heights on the night of 26-27 July, 1916. Lasting continuously for over 12 hours the Australians and the British exchanged grenades with the Germans, with the Allies alone throwing over 15,000 Mills grenades during the night.
During WW1 there were several improved versions including the No.23 which had an improved base cap with a rod thread allowing the grenade to be adapted as a rifle grenade, and later the No.36.
The No.23 Mk.II is 4.25 inches long, 2.75 inches wide, and has a circumference of 7.5 inches at its most bulbous point, and has a hefty weight of some 1.5 lbs when empty.
The photographs show the No.23 Mk.II primed and ready, and also the disassembled grenade showing the various parts including the Striker, The Striker Spring, the Striker Lever, the Safety Pin, the Filler Hole Cap and the Base Cap with the Maker Mark of ' D. and B ' for Dobson and Barlow, and the type designation ' No.23 MK.II '.

LF

[Lancashire Fusilier]

Mills Bomb - Workings diagram.

Mills Bomb - Detonator storage tin.

[Lancashire Fusilier]

Mills Bombs ( Hand Grenades ) - Bombing Parties.

How to throw a Mills Bomb - note the canvas storage bucket, holding 24 bombs.

[Lancashire Fusilier]

Sir William Mills ( 1856 - 1932 ).

Dobson and Barlow, Bolton, Lancs.

[Seadog]

And:

[Lancashire Fusilier]

And:

Cut-away examples are excellent.

Regards,

LF

[Seadog]

Thanks for posting the fuse container and the photos!

Norman

[Lancashire Fusilier]

Thanks for posting the fuse container and the photos!

Norman

My pleasure,

Regards,

LF

[RobL]

Very nice, thanks for sharing. Interesting how the bombers wearing the vest with soft caps still have a No 1 or No 1 Mk 2 (short handle No 1) bomb, when surely the vest indicates the Mills bomb is now in use?

[Lancashire Fusilier]

Very nice, thanks for sharing. Interesting how the bombers wearing the vest with soft caps still have a No 1 or No 1 Mk 2 (short handle No 1) bomb, when surely the vest indicates the Mills bomb is now in use?

RobL,

Good point, I assume the sack contains more No.1s ?

Regards,

LF

[tootrock]

I note from the instructions that the grenade is to be held in the right hand, base plug uppermost, so that the pin could be pulled with the left hand.

This would suggest that the lever was only held down by the web between thumb and forefinger, not very securely. If held up the other way, all four fingers would hold the lever, which seems much safer.

Any comments?

Martin

(Who has never held one himself).

[Lancashire Fusilier]

I note from the instructions that the grenade is to be held in the right hand, base plug uppermost, so that the pin could be pulled with the left hand.

This would suggest that the lever was only held down by the web between thumb and forefinger, not very securely. If held up the other way, all four fingers would hold the lever, which seems much safer.

Any comments?

Martin

Martin,

You make an interesting point regarding the printed instruction.

I just checked the procedure on my grenade, and with the safety pin inserted from the other side to that shown in my photographs ( the safety pin can be inserted from either side ), and holding the grenade in my right hand with the base cap at the top, and with my right thumb on the base cap, all 4 fingers on my right had can firmly grip and hold in place the Striker Lever, leaving my left hand free to pull out the safety pin away to the left side of my body. I can then throw or lob the grenade with my right hand.

Regards,

LF

[Lancashire Fusilier]

Martin,

Here is a new photograph of the grenade with the safety pin inserted from the other side so as to match the instructions given in the 1917 booklet, and it is the better way for a right handed thrower.

Also, when gripping the Striker Lever with the 4 fingers of the right hand and pulling it towards the grenade body for that fraction of an inch, it releases the pressure on the safety pin, moves it away from the Striker Lever and allows it to be pulled out easily.

Regards,

LF

[calibre792x57.y]

Very nice, thanks for sharing. Interesting how the bombers wearing the vest with soft caps still have a No 1 or No 1 Mk 2 (short handle No 1) bomb, when surely the vest indicates the Mills bomb is now in use?

Well the vest does not necessarily indicate that the bombers are using the Mills grenade - they could have the No. 15 or 16 in those pockets for example. Indeed the No.6 and 7 seemed to have been issued packed into 10 pocket waistcoats according to the Training and Employment of Grenadiers issued by GHQ in October 1915, at which time the No1 Mk II and Mk III were still in frontline service.- SW

[Lancashire Fusilier]

Baratol is an extremely dangerous high explosive, and once poured into the grenade body through the filler hole at the top of the grenade, it sets hard like concrete, and is extremly difficult to remove, something that should only be undertaken by a trained professional.

Here is an interesting photograph of a dismantled WW2 grenade, showing the different components, including a small pile of the hardened Baratol which had been removed from inside the grenade!

LF

[Lancashire Fusilier]

2 photographs, one shows the staff of the Mills Munitions Factory in Bridge Street West, Newtown, Birmingham, which supplied the 'Mills Bomb' hand grenade to the British and Allied armies throughout the war.

The other photograph shows women manufacturing grenade base plugs at the Mills Munitions factory in Birmingham.

LF

[RobL]

Love the photos of the munitions works, thanks all for the info. Any truth in each box of bombs having a tin of vaseline for lubricating the fuses when fitting them?

[Tom Morgan]

LF - While not questioning your knowledge of the weaponry (which far surpasses my own) I'd raise a doubt about your account of how the bombing team worked. Rather than "race down the trench throwing grenades into each dugout they passed, killing the occupants," the bombing team would first have to deal with the live germans who were up in the trench. The ones in the dugouts would be dealt with by "moppers up" following behind.

The bombing team worked as follows - the two bombers threw a couple of bombs each into the next bay, waited for the explosions and then the two bayonet men led the immediate rush round the corner into the next bay, killing anyone who was still alive, before the process was repeated, bay by bay. This is the kind of activity going on when we read accounts of an group of men "bombing their way up the comminication trench, etc. Very dangerous work.

The moppers up followed on behind, calling on the occupants of dugouts to come up and surrender, throwing in bombs where there was a refusal or no reply.

Tom

[Lancashire Fusilier]

Love the photos of the munitions works, thanks all for the info. Any truth in each box of bombs having a tin of vaseline for lubricating the fuses when fitting them?

RobL,

Yes, I have previously seen a reference to Vaseline being kept in the Mill's bomb storage crates/boxes and being used to lubricate the threads on the grenade's base plugs.

Vaseline was also very much a part of the Grenadier/Bomber's box of tricks, and was used in connection with several WW1 explosives, for example :-

Lyddite - which consists of melted or solidified picric acid, and Vaseline was used to melt it.

Ballistite - consists of guncotton plus campher or Vaseline.

Cordite - consists of nitro-clycerine 55 parts, plus guncotton 37 parts, plus Vaseline 5 parts, plus acetone to harden.

It may also have been used to lubricate fuses ?

Regards,

LF

[David B]

LF,

great explanation. One point though. Why is Baratol dangerous (ignoring the obvious) - was it unstable ? likely to go off at the slightest provocation ?

If this was the case would not Mills bombs have to be carefully handled, which would tend to obviate the handling they would receive when being transported or carried.

Cheers.

[Lancashire Fusilier]

LF,

great explanation. One point though. Why is Baratol dangerous (ignoring the obvious) - was it unstable ? likely to go off at the slightest provocation ?

If this was the case would not Mills bombs have to be carefully handled, which would tend to obviate the handling they would receive when being transported or carried.

Cheers.

David,

All explosives are extremely dangerous, I was really mentioning it in the context of the rest of the post as it related to the Baratol being removed from the grenade only by a professional.

I would hate to think of anyone prodding around in an old grenade trying to get the hardened Baratol out with a screwdriver or knife!

Strict precautions were taken with the Mills bomb, by keeping the fuses completely separate and stored in a Fuse Tin during transportation, and only fitting the fuse into the grenade before intended use.

Regards,

LF

[David B]

LF,

Thanks. I had the impression that you thought that Baratol was more dangerous than other explosives, satisfied now. Cheers

[auchonvillerssomme]

This throwing instruction is slightly later and seems a lot safer than the 1917 instructions cited above. Holding the lever in the palm of the hand rather than by the fingers would be far safer in wet, mussdy and cold conditions.

[calibre792x57.y]

I wouldn't get too excited about the filling of LF's bomb - the vast majority of Mills grenades No.s 5 and 23 are filled with ammonal or amatol, usually the former, not baratol. The remnants of the pink paint on LF's grenade show that it was one of these. Baratol was used for grenades intended for use in tropical conditions and these were marked with a green band and had a hatched 'filled' band, generally red, although very early ones are said to have yellow hatching on a solid red band but I have never seen one of these. It is much more stable than those based on ammonium nitrate and is generally found in late No.23 Mk III or No.36 Mk I. Even then it was much more common in post- War examples. Although it is a solid filling there is a simple and safe way of removing it which I won't go into. SW

[Lancashire Fusilier]

Tom,

On the contrary, I am sure you know much more on this subject than I do.

However, in my files I have a booklet, published in 1917 by a Major Graham M. Ainslie, and his booklet deals extensively with grenades and trench warfare, which he says are " based on his practical experiences in the present war ".

Here are extracts from his publication dealing with trench bombing, and trench raiding, which I am sure you will find it most interesting.

Regards,

LF

Composition of a Grenade Squad

In Line In Single File

No. 1 Bayonet Man No. 1 Bayonet Man

No. 2 Bayonet Man No. 2 Bayonet Man

No. 3 First Thrower No. 3 First Thrower

No. 4 2nd Thrower No. 6 First Carrier

No. 5 NCO or Leader No. 5 NCO or Leader

No. 6 First Carrier No. 4 2nd Thrower

No. 7 2nd Carrier No. 7 2nd Carrier

No. 8 Spare Man No. 8 Spare Man

No. 9 Spare Man or Sniper No. 9 Spare Man or Sniper

Duties of above - Nos 1 and 2 Bayonet Men

1. Clearing of a Trench to a Flank.

They are the bodyguard of the Thrower and Carrier and must always protect them under any circumstances and at all costs.

Note The latter are not armed against attack at close quarters. The Bayonet Men work in advance of the Thrower and Carrier of their squads. They act as trench scouts; that is, they instruct the Thrower and Carrier how the Trench runs and where the dug-outs and side trenches will be met. They will carry their rifles with bayonets fixed, loaded, magazine full.

No. 3 and No. 6 bomb and clear all dug-outs on the way down the Trench. The first man throws the bomb, and the Bayonet Man enters the dug-out and completes the work. At the junction of the communications trenches and side trenches they act as sentries and observers until relieved by the squads in rear. If necessity arises, they assist the Thrower by throwing bombs.

2. Frontal Attack Against Enemy Positions.

They will be in line with, not in advance of the Thrower and Carrier and will protect them while throwing by snap shooting or with their bayonets against assault, or a sudden rush by the enemy when at close quarters.

3. Street Fighting or Village Cleaning.

They will keep down enemy rifle fire by snap shooting, so as to enable the Thrower to work close enough to his objective to throw grenades, and when these have burst, will go forward and complete their work.

No. 3 First Thrower - He throws grenades according to the directions give him by his leader or bayonet men. He is a picked man, steady under fire and chosen for his accuracy and length of throwing.

No. 4 The Carrier - He follows close enough in the rear of the throwers to keep them supplied with grenades, but must be careful not to crowd them or impede their throwing. He will be prepared to instantly take up the duties of the thrower should he become a casualty.

No. 5 The N.C.O. or Leader - He is responsible for his squad and the proper carrying out of the duties given to the squad. He will inspect each man before an attack and see that he has his complete equipment and that he knows the general idea and direction of the attack and the final objective of his squad. He will be responsible for the maintenance of supplies of grenades through his squad to the thrower, and will supervise the automatic filling up casualties in the squad by men from the squads in the rear. He will indicate the position of his squad in the attack to the supporting troops, etc., by means of flags or other signal by day and by coloured flares at night.

Nos. 6, 7, 8 and 9. Their duties are the same as Nos. 1, 2, 3 and 4, and are considered primarily as carriers until otherwise employed.

No. 10 - Spare Man. He will act , if necessity arises, as leader of his section, to clear side trenches, etc., and will instantly take over the duties of No. 5 should he become a casualty.

No. 11 - Sniper. He will act as a sniper by day and a connecting file by night, between his squad and the squad of troops in rear.

Note. Every man in the grenade squad should be trained to fill the position of any other in the squad.

The position occupied by the grenadiers in an attacking squad has this main point in consideration, the safety and local protection of each individual in the squad; care should be taken that as far as possible each man has a solid corner of the trench close to him, which he can use as protection against the bursting effect of enemy grenades, by quickly advancing or retiring around the corner.

The bayonet men are in advance of the thrower, close enough to protect him, and not too far in front of him as to be in danger of being bombed by him.

The Thrower - the actual means of attack - is protected in front by the traverse and in the rear by the corner of the Parados. The Carrier is close behind the Thrower and is protected by two corners. The N.C.O. or Leader is where he can best watch the flight of the grenades thrown by the Throwers, and is also equally protected.

Method of Advance - It is usually the endeavour to bomb and clear three bays at a time in advance of the bayonet men. The N.C.O. reports the throwing by the word " Mark ", to indicate a burst in the required bay. On the third " Mark " having be registered, the N.C.O. gives the order " Bayonet Men Report ". They immediately advance up to the last bay cleared and report back after examination either " All Clear " or " Enemy Holding ", whereupon the N.C.O. gives the order " Advance " , or directs the Thrower to bomb the last bay again. This means of advance is continued until the objective is gained.

Island Traverse - It is imperative that the attack must not be allowed to be held up, and should it be found impossible to advance down the trench itself, owing to enfilade fire, the attack must be immediately launched outside the trench, so as to attack the traverse from the rear, in the case of a daylight attack.

Precautions - Care must be taken, especially by the bayonet men in their advance through the trench, that enemy concealed trenches, dug-outs, etc., are not left undiscovered. The sides of the trench and the walls and floors of the dug-outs should be carefully examined for concealed entrances and exits.

Frontal Attack - In conjunction with Infantry -

The preparation before the attack - the following details must be carefully considered :

(a) The study of operation orders.

( b ) The linking up of observations gained from the :-

1. The study of existing trenches and aeroplane maps of enemy positions.

2. The personal reconnaissance of the topographical features of ground to be covered in the advance.

( c ) The detailing of squads to their special objectives and the arranging of work, carrying wire and demolishing parties for permanent blocks at the final objective.

(d) The kind of grenades to be used with the view to facilitating the carrying of same.

(e) Carrying parties must be told off to insure supplies of grenades reaching the throwers.

(f) Grenade Depots must be built, sign boards arranged for, and clearly marked " Grenade Depot " not only in our own system of trenches, but also the positions told off beforehand where they are to be established in the enemy trenches, or in No Man's Land immediately previous to the attack.

(g) Responsible officers and N.C.O's should be told off to look after Grenade Depots and supply of grenades.

(h) The position for infantry grenade dumps must be selected and clearly explained to all units taking part in the attack, and special parties told off to collect at these points and carry grenades to nearest depots.

(i) A traffic system should be arranged and all men must be acquainted with it, and the trenches or lanes of travel clearly marked " up traffic, " etc.

The Advance

1. In line with infantry

2. In advance of infantry

No. 1 is the method adopted in daylight attack, the advance not being covered by gas or smoke clouds.

No. 2 is the method adopted in night attacks and when weather conditions or topographical features of ground covered in the advance allow it.

Attacking squads are allotted positions in lines of infantry immediately opposite their final objectives, and on reaching these positions should immediately commence bombing and clearing the trenches towards their final objectives.

In the case of No. 1, the infantry clear the main trench, but special grenade parties may be told off to assist the infantry at their work especially when strong points occur in the enemy position. It is most important that all infantry taking part in the attack should be previously supplied with grenades and this must be considered the first source of supply.

Positions designated as infantry grenade dumping positions should be chosen and known to the infantry at which they dump their grenades in their advance on the enemy position. These positions should be close to the position to be captured and held.

In order to hold positions captured from the enemy it is imperative that grenade storming parties hold their final objectives at all costs, and until positions to be permanently held have been consolidated.

Trench Storming Parties

Trench storming parties should kill or drive back the hostile occupants of a trench as quickly as possible. clear as much of the enemy trench as has been ordered, and then hold the position cleared with as small a loss as possible to themselves.

It must be remembered that it trench clearing, and especially in deep and narrow trenches only the head of the attacking party can directly kill, and seldom more than one man can throw at a time. Therefore it is essential that a constant supply of grenades reaches the thrower and that places of casualties are automatically filled by reinforcements. Men must be trained until they can do this either by day, or at night.

Advance.

Movement is rapid until contact with the enemy is obtained. Once contact is established it must be maintained and pressed home. A retreating enemy must be given no time to re-establish a defensive attitude, corners must be worked carefully and bays and straight pieces of trench rushed. The bayonet men will complete the work of the grenades and see that the carrier and thrower will meet with no opposition on their way to new throwing position. The effect of a bursting grenade in a confined space like a trench is tremendous, and though it may not kill it will stun or shock the hostile occupants, and if the bayonet men follow up rapidly they will meet with very little resistance.

Casualties

Every man must be trained to take up the duties of any other man in the squad. They do not necessarily keep to their own squads; the squad in rear of the attacking squad may be looked on as a reserve squad for the one in front. Thus, Casualty first squad. The thrower No.3 is reinforced by the first thrower of the second squad, and so on.

Side Trenches

When a side trench is met with, the leading squad will go up and clear it. The second half will remain at the junction until first returns, then the second squad will continue advance in original direction of the attack.

Blocks and Barricades

For blocking captured trenches, etc., see Manual of Field Engineering, Wire Entanglements, Hurdles, etc.