Category Archives: Ordnance

2″ High Explosive Mortar Bomb

Continuing our in depth look into the 2” mortar, tonight we are considering the 2” High Explosive Bomb. The 1959 manual gives the following description:

The HE bomb has a buff painted body with red and green bands around it and a white metal unpainted tail. The head of the bomb is covered by a screw-on safety cap, underneath being a safety pin. The name, mark, lot number and date of manufacture are painted, in black, on the body. There is a cartridge in the tail which when fired propels the bomb.As can be seen, my example does not have any black markings on and the fuze is prominently marked ‘DUMMY’:As in the description a white metal alloy cap is provided, with raised lettering instructing the operator as to which way to turn the cap:The fuze is threaded with the opposite type of screw thread so turning it the wrong way removes the whole fuze from the bomb body. On a live bomb a No 161 percussion fuze is fitted, as illustrated in the 1959 manual:Despite the manual saying that the tail was to be left in unpainted metal, one side of the vanes are painted red:Interestingly this is specifically referenced in a diagram from the same 1959 manual:The tail unit contained a single cartridge to propel the bomb, with a screw on cap to protect the cartridge once fitted. Makers marks were stamped onto the vanes, but have proved very hard to photograph (trust me they are there):The 1939 army pamphlet noted:

The number of bombs which can be carried is strictly limited owing to their weight. They should be used sparingly and only as part of a definitive plan…Rates of fire depend on wind and circumstances. The maximum rate with accuracy is from three to four bombs a minute. The distance which the HE bomb is practically certain to be effective against personnel in the open is about eight yards in all directions form the point of burst. Large fragments may, however, have sufficient velocity to inflict wounds up to 150 yards or more, particularly if the burst is on stony ground.

2″Parachute Illuminating Mortar Round

The 2” mortar was to remain in British Army service from 1937 until it was replaced by the 51mm mortar in 1981, it was a very simple but effective weapon and as time went on a large range of specialist rounds were developed for the mortar including drill, smoke, high explosive and the subject of tonight’s post, the parachute illuminating mortar round. As might be expected from the title, these rounds were fired into the air where an illuminating flare was deployed attached to a miniature parachute that let it gently drift down over the battlefield providing bright illumination at night. The round itself is similar to other 2” mortar bombs, with a thin metal tube attached to a tail unit:imageThe tail has a ballistite cartridge in it that when fired provides the force needed to launch the bomb out of the tube, a small screw on cap was provided to prevent accidental detonation:imageMetal fins on the tail of the bomb help stabilise it in flight allowing the bomb to be dropped accurately on the target:imageThe walls of the bomb are made of thin steel, in this case pained white with a red band and black markings:imageThese indicate that it is a 2 inch Mortar Illuminating Round. A filling date stencilled on the body shows this example dates from 1963:imageThis bomb has been fired and the contents are therefore missing from the bomb case, however originally the parachute illuminating round had the following internal components:2in-13_zpsa5c59d0dDuring the Second World War these bombs were delivered in cardboard tubes, by the 1960s these were replaced with metal tins which offered better resistance to moisture:imageAs can be seen the contents are stencilled onto the outside of the storage tube, inside a plastic liner helps prevent the bomb from rattling around:imageThe date ‘1965’ is stamped into the base of the storage tube:imageThis is my first mortar round and I think I have started off with a particularly nice example.

No 68 Drill Grenade

By 1940 it was obvious that the Boys Anti Tank Rifle was completely obsolete. It would take time to develop a new anti-tank weapon (what would eventually become the PIAT) and what was needed was something in the interim that was cheap to produce, effective against armour and could be got out to troops rapidly. The design that was eventually produced used the SMLE cup discharger (normally used for throwing Mills bombs) to fire a grenade holding a shaped charge at short range. Although often forgotten today, the No68 Grenade as this new weapon was called, was a major technological leap forward when it was introduced, even if two years later it had been superseded by technology. The manual instructed troops:

The No 68 A.Tk Grenade has been introduced with the object of damaging hostile AFVs. It is fired from the discharger fitted to the service rifle, a 30-grain ballistite cartridge being used.

The grenade itself consists of a small die cast cylinder, with four stabilising finsimageAnd a circular iron plate on the end to allow it to work with the cup discharger:imageAs can be seen this example is painted white, indicating it is a drill grenade. This is also indicated by the large holes bored into the head of the weapon to show it is free from explosives:imageThis example is solid inside to allow troops to practice firing it safely, the live examples used a shaped HEAT projectile, as illustrated in this contemporary diagram:no68planThe round had to hit the target at an angle of +/- 15 degrees and had a range of about 50 yards so the user had to be exceptionally brave to use it! The manual instructs:

It must be realised that the ballistite cartridge used in conjunction with the grenade gives a considerable recoil; and, owing to the flat angle at which the rifle must be held it is essential to place the butt of the rifle against a sand bag or similar object…

Considerable initiative must be displayed in preparing positions from which to fire the grenade. These may be from behind low cover, from trenches or from the loopholes of pill-boxes. no68-grenadeReturning to my example, it can be seen that there is a split pin and pull ring on the grenade fin:imageThis again mirrors the live example where these were used as a safety pin to prevent premature detonation. The fins themselves have the grenade type cast into them:imageAnd the date of manufacture, 1942:imageAlthough it is hard to make out there is a small cast ‘PDC’ on the base of the fins:imageThis stands for ‘Patent Diecasting Co’ who were one of the companies who manufactured the grenade bodies. The grenade eventually reached a Mk VI version and was removed form service by 1945, although by that point it was really only the Home Guard who made use of them. About 8 million of these grenades were made in various types, the training ones are uncommon but still around as they were used by the Home Guard and not always returned to stores!

7.62mm Drill Round

In order to safely test and demonstrate a firearm inert rounds are needed that can be cycled through the action. These rounds need to be the same weight and shape as a live round, but clearly distinguishable to prevent any mix ups- the dangers of feeding a live round through a weapon in a classroom are easy to appreciate! Drill rounds form the 1930s onwards, in the UK at least, have followed a fairly standard set of parameters. They have silver rather than brass cases, a series of grooves let into the sides of the case so the user can tell by touch alone they are drill rounds, and a recess on the base where the percussion cap would normally be. Tonight we are looking at a pair of drill rounds in NATO standard 7.6nmm calibre:imageThese conform to the standard design of such rounds and by looking at the head stamps we can see that they were manufactured in 1964 by the Royal Ordnance Factory Radway Green in Cheshire:imageAs can be seen these rounds are marked ‘L1A2’ and this particular drill round was introduced in June 1956 for use with the new SLR rifle, it had shallow grooves around the cartridge, each filled with red paint to make the round visually distinctive:imageThe bullet has a lead core and is secured with a double cannelure at the neck. Wood is fitted inside the case to help support the bullet. Experiments were undertaken in the 1970s to produce a cheaper and more robust drill round with the wood replaced with plastic, but these were never adopted into general service.

25 Pounder Shell Casing

Arguably the best all round field gun in use by the British Army in the Second World War was the 25 pounder. The 25-pounder fired “separate”or two-part ammunition—the projectile and the propelling charge in its (usually brass) cartridge case with its integral primer were loaded separately. The following description of the case comes from the 1940 handbook for the gun:

The Mark II case is of solid-drawn brass slightly tapered from the base to within 1.1 inch of the mouth, where it is cylindrical. The base is recessed, bored centrally and screw-threaded to receive the percussion primer; it projects circumferentially to form a rim by means of which the extractor of the breach mechanism automatically ejects the case when the breech is opened after firing.

I have just one of these cases in my collection:fullsizerender1There were two types of cartridge. The “normal” cartridge contained three cloth charge bags (coloured red, white and blue). White or blue bags would be removed from the cartridge to give “charge one” or “charge two”, leaving all three bags in the cartridge case gave “charge three”. The cartridge case was closed at the top with a leatherboard cup. The second type of cartridge was “super”, which provided one charge only. The cup could not be removed from the cartridge case. In 1943, an incremental charge of 5.5 oz (160 g) of cordite (“super-plus”) was introduced to raise the muzzle velocity when firing armor-piercing shot with charge super; this required a muzzle brake to be fitted. Adoption of “upper-register” (high-angle) fire needed more charges to improve the range overlap. This led to the development of the “intermediate increment” of 4oz cordite, which was introduced in 1944. The bags were striped red and white to indicate that they should only be used with charges one and two. When one bag was used with charge 1 it provided charge 1/2. When one was added to charge 2 it provided charge 2 1/3, and two bags, charge 2 2/3. This allowed a range of seven different charges instead of four.800px-25_pounder_base_charges_diagramsLike all British shell cases, mine has a wealth of headstamps on the base:fullsizerenderFrom these we can see that the shell casing was manufactured in 1942 and includes the lot number so a faulty batch of ammunition and casings could be tracked down later by the markings. In this photograph of an Australian 25 pounder at El-Alamein in 1942, a large pile of discarded shell casings can be seen in the foreground:2-8_field_regt

30mm Aden Cannon Link

The Aden Cannon was developed in the immediate post war period to provide a weapon with a much higher rate of firepower than wartime aircraft cannon. The ever increasing speed of fighter jets meant that a weapon was needed that would put as much firepower on the target in as short a space of time as possible as closing speeds were so much higher and time on target so much shorter than anything that had come before. ADEN stood for Armament Development Establishment, where the Cannon was developed, and Enfield where it was produced and the cannon had a rate of fire of between 1,200 and 1,700 rounds per minute depending on model.

The weapon had a revolving chamber and fired 30mm shells that were linked together by a set of disintegrating links and it is one of these links we are considering tonight. The link is made of blackened pressed steel and is about 4 inches in length:imageThe design is different from any used previously as each link is joined by hook and eyes. The link is marked ‘RG’ and ‘Mk 1’ indicating it was made by the Royal Ordnance Factory, Radway Green in Cheshire:imageThe link has deep pressed grooves in the metal to help it maintain rigidity and to increase its strength without increasing the weight:imageThe shell itself was a small, short round with an overall length of 199mm which had a relatively low velocity; it was developed from the Second World War German 30x50B cartridge used with the Mauser MG 213C/30 cannon.

The ADEN cannon was first introduced into general service on the Hawker Hunter in 1954 and was used on nearly every frontline fighter in the RAF until the Tornado in the 1980s. The weapon is still in widespread use across the globe with various different air forces.94870

Practice 1.5″ CS Gas Cartridge Case

CS gas was developed by the British at Porton Down in the 1950s and 1960s as a non-lethal riot control agent based on the discovery of the compound by American scientists in the 1920s. CS Gas reacts with moisture on the skin, in the eyes, nose and mouth, and in the lungs, causing a burning sensation. Apart from the pain it causes it also results in tears being shed as the eyes go into an automatic cleaning mode. In severe cases coughing and vomiting can occur, especially if the victim is confined to an area of high concentrations of the gas, such as a room. The effects wear off within a few minutes of reaching clear air. The use of CS gas came to prominence in 1969 when it was used to quell civil disorder in Northern Ireland during the so called ‘Battle of Bogside’. The British Army made extensive use of CS gas during the troubles and used both grenades and fired canisters from their Federal Riot guns. As usual with a weapons system, troops need to train on it under controlled circumstances so inert cartridges were produced that only released pink smoke, rather than actual CS gas. These training rounds were clearly marked:imageThe cartridge case is made of aluminium, 1.5” in diameter and has a pair of coloured bands, blue over green. As can be seen it is clearly marked as being an irritant practice round. The rear of the cartridge gives a filling date of October 1974:imageTurning to the base of the cartridge we can see that the casing itself dates from July 1973 and has a head stamp marking of FPL:imageThe CS projectile itself was a separate piece of ordnance that fitted inside this casing, the cartridge case holding the percussion cap in the base and a propellant charge. When fired at a distance of 100m the cartridge had a delay of between 1 and 5 seconds and then burnt, expelling the CS gas for between 10 and 15 seconds. During the Fall Curfew of 1970 the British Army had fired up to 1,600 canisters of CS and following its use at Lenadoon in 1972 the RUC and British Army ceased using CS gas in Northern Ireland. The Royal Scots report ‘Internal Security training for Northern Ireland’ explained:

When CS gas is thrown in open spaces, such as post war housing estates, it needs to be used in considerable quantities to be effective…

Later the Battalion commander would remark that one of the more damaging consequences of using CS gas was the potential

for it to blow the wrong way and end up in old people’s houses.

Despite the decision to stop using it in Northern Ireland, munitions and training continued in case it was needed at a future date.