Posted 07 April 2004 - 01:41 PM
Something I threw together a few years back:
Many new weapons appeared for the first time during the period of the First World War, 1914-1918. Many of these weapons were little more than improvements upon older designs and soon became obsolete as newer, more modern weapons were introduced to the ranks of the opposing armies.
One new weapon introduced by the German Army during the war, which proved to be very successful, was the “Granatenwerfer", literally the grenade thrower. This particular weapon was developed in response to specific needs placed upon the troops by trench warfare. The design was simple and the weapon soon became a favorite of the soldiers and universally accepted. It proved to be an effective weapon both in its defensive role and its offensive role.
When the “Granatenwerfer” was first introduced into service it was known as the “Priesterwerfer” or Priest thrower. It received this unusual designation because the original concept of this weapon came from a Hungarian Priest. He developed it for use in the static trench warfare that had been in place since late 1914.
The weapon was then tested by the German Army in 1915 and introduced throughout the army with the official designation, ‘Granatenwerfer M1915'. The intent was to provide at least one ‘Granatenwerfer 15' to every infantry company in the army. The weapons would be manned by men taken from the ranks of the company it was assigned to. Each gun would be under the command of a non-commissioned officer, a No. 1 man would be in charge of aiming and firing the gun and a No. 2 man would be responsible for the ammunition supply.
The main difference between the Granatenwerfer and other trench mortars of the time was that the 1915 pattern stick-bomb (Wurfgranate 15) was fired from a rod instead of from out of a tube, it was essentially a spigot mortar. The entire weapon could easily be broken down into two main parts; the bedplate and the firing assembly. The weapon was accompanied by a case containing tools and spare parts.
The Bed plate
The bedplate was circular in shape and made of sheet iron and weighed about 48 lbs. It had a semi-circular flange underneath, which was intended to take up the recoil. This flange should have been well sunk into the ground before firing. There was a handle opening on the edge of the bedplate that was used to transport the bedplate to another location. A semi-circular collar was riveted onto the top of the bedplate. The bomb-thrower was attached to this collar.
The Bomb thrower
The bomb-thrower was made up of the following parts: The “Stick”, clinometer, trunnions and traversing arc. The entire mechanism was attached to the bedplate using two clamp screws. The bomb-thrower weighed about 31 lbs.
Firing the Weapon
After setting the bedplate firmly into the ground the bomb thrower mechanism was attached to the collar assembly using the two clamp screws. The operator would press down the cocking collar until the firing hook catches. The safety catch would then be turned down until the letter S (Sicherung=safety) was visible.
The clamp screws were then loosened and the traversing arc was brought to the point desired, the clamp screws were then tightened. The operator would then set the pointer of a water level to the degree corresponding to the range desired then adjust the level of the “Stick” by raising or lowering it. When the level of the ‘Stick’ corresponded to the desired angle the “Stick” would be clamped down.
The bomb would then be placed upon the “Stick”. On the command “Ready” the tape on the safety pin was removed, then the pin was removed. The firing lever was turned in the direction of which the firing was to be carried out and the lanyard was attached.
In order to fire the Granatenwerfer the safety catch had to be turned up until the letter F (Feuer=fire) was visible. The crew was directed to take cover and the lanyard was given a sharp jerk that fired the bomb. This procedure was repeated as often as needed.
The 1915 Pattern stick-bomb
The stick-bomb or grenade is made up of a malleable cast iron body; a tail made of tubing with four vanes of sheet iron at the base. There is a recess for the percussion fuze with a 2.5-gram detonator at the front of the grenade and a recess for a cartridge inside of the tubing at the rear. The grenade itself is fired using a standard service rifle cartridge with the bullet removed; the powder charge remained the same, 3.2 grams. The shape of the segmented body of the grenade with its tail fins reminded British troops of a pineapple, hence the nickname given to the weapon.
The grenade had a bursting charge of nitrate of ammonia and TNT. The fragmentation effect depended upon the angle being used to fire it. The fragmentation spread in low trajectory shots was from 3-5 meters wide and 50 meters long. Steeper shots generally had a fragmentation spread of 30 meters from impact. The Model 1915 grenade generally made a small impact crater upon impact.
The stick-bombs were packed in wooden cases containing ten bombs. The percussion fuzes were screwed in and a blank cartridge was inserted. The cases also contained 10 detonators in a special waterproof box.
The bomb was prepared for use by unscrewing the fuze and inserting a detonator. The fuze was screwed back in and any bent wing vanes were straightened with flat-nose pliers. The fuze was a simple impact variety. When the granatenwerfer was to be used the stick-bombs were prepared for firing. After the thrower was set up the fuze was unscrewed and the detonator was inserted. The fuze was screwed back in and the stick-bomb was ready for use.
The fuze consisted of a percussion cap, safety spring, striker, compressed powder pellet and detonator. Upon impact the safety spring was compressed and the striker would hit a percussion cap. The flash from the percussion cap would pass through the compressed powder pellet and set off the detonator. The stick-bombs were never to be transported with a detonator or without the safety pin and safety pin tape in place.
Later in the war a new projectile was developed which made the grenade more effective against enemy personnel. Instead of having an impact fuze at the end of the grenade the newer model was designed to rebound off of the ground and explode in the air.
This was accomplished by fitting a steel case over the head of the cast iron body of the grenade with the end closed. The case contained a charge of black powder. When the grenade struck the ground the black powder would be ignited through an opening in the fuze just before the grenade detonated. The steel case surrounding the bomb would act as a mortar tube, propelling the grenade into the air where it would detonate. This Pattern of bomb did not have the exterior segmentation as in earlier models; instead the segmentation was along the interior walls of the bomb. Exterior segmentation would have seriously reduced the “mortar” effect of the bomb after it had struck the ground.
One other difference between the Model 1915 grenade and newer rebounding grenade was the method of firing it. Instead of using a standard rifle cartridge a small flat tin case containing propellant was inserted into the base tube. This allowed for more room for the bursting charge. Other differences include extending the length of the bomb from 10.8 inches to 14.1 inches and reducing the diameter from 2.7 inches to 2.6 inches.
One of the shortcomings of the new rebounding bomb was the reduction in range from 328 yards down to 275 yards.
Details of the Pattern M1915 bomb and New Pattern Rebounding bomb
New Pattern (Rebounding) Ordinary Pattern, M. 1915
Total weight 5½ lbs. 4 lbs.
Weight of bursting charge 7 oz. 8 oz.
Total length with fuze 14.1 in. 10.8in
Exterior diameter of body 2.6 in. 2.7 in.
Maximum range 275 yards 328 yards
Range Table for 1915 or 1916 Pattern Bomb-Thrower with 1915 Pattern Stick-bomb
Range Elevation in degrees Range Elevation in degrees
Meters Yards High Angle Fire Direct Fire Meters Yards High Angle Fire Direct Fire
300 328 45 45 170 186 73 18
290 317 47 42 160 175 74 16
280 306 50 38 150 164 75 14
270 295 53 34 140 153 76 -
260 284 56 31 130 142 77 -
250 273 59 29 120 131 78 -
240 262 62 27 110 120 79 -
230 251 64 25 100 109 80 -
220 241 66 24 90 98 81 -
210 230 68 23 80 87 82 -
200 219 70 22 70 76 83 -
190 208 71 21 60 66 84 -
180 197 72 20 50 55 85 -
The weapon was not to be fired at ranges less than 55 yards in order to avoid endangering their own troops.
The Bomb-thrower was redesigned in 1916. The new model Bomb-thrower, called the Granatenwerfer 16, was easier to operate than its predecessor but it still was unusually heavy. The newer pattern actually weighed more than the 1915 Model, about 88 lbs.
The bed plate
The new bedplate was circular with the front being flanged. There was a handle attached to the front along the flange to be used in carrying the plate. When the bomb-thrower was being prepared for action the flanged edge was placed firmly in the ground. There were two range tables on the bedplate, one for high angle fire and the other for flat trajectory fire.
The bomb-thrower consisted of the “stick”, the clamping arrangement and the sole plate with the clinometer and V-shaped back sight. The limits of elevation were +85° to +14°
The Traversing arc
The traversing arc revolved on the bedplate and was secured to it by a vertical clamp screw with handle. The limits of traverse were 80° to the right and 80° to the left.
Firing the ‘Granatenwerfer 16'
The crew should take care that the “stick” was screwed in firmly before firing was attempted. Since there was recoil when the Granatenwerfer was fired it was recommended that it be operated from the side, preferably the left so that the graduations on the clinometer could be read. The recoil could be checked by a sandbag, however, it should be placed sufficiently far back to allow the bomb-thrower to slide freely on the bedplate so that the position of the bedplate did not alter.
The bedplate itself was placed on the ground with the flanged edge and handle facing forward and the flanged edge firmly sunk into the ground. When properly set up the bomb-thrower should move easily on the bedplate.
Once the stick was placed in the proper position for firing and the angle was set the cocking handle would be thrown sharply against the fore stop. This action automatically cocked the “stick” and set the weapon on safety, the letter S could be seen (Sicherung = safety). The Granatenwerfer bomb would then be placed on the “stick” and the safety pin would then be removed from the bomb. Throwing the cocking lever sharply against the backstop could disengage the safety cam on the cocking lever. The side painted red and marked with an F (Feur=fire) would then be visible.
The bomb would be fired giving the lanyard a sharp jerk. An indicator bolt moved to the right showing that the bolt had been released. The bomb-thrower would then have to be pushed up hard against the traversing arc, as it would have jumped back when fired.
It was a relatively simple method; the basic movements were pushing the cocking handle forward then back before firing. The maximum rate of fire was reported to be 250-300 rounds per hour.
Instructions for the employment of the Granatenwerfer
The Granatenwerfer was considered to be a very valuable weapon for trench warfare. It soon became very popular among the troops because of its excellent rate of fire and the explosive effect of the bomb. It was also able to propel a grenade much further than could be achieved simply by throwing it by hand. Due to its range the ‘Granatenwerfer’ was normally placed in either the first or second trench. This offset the slight disadvantage of the heavy weight of the base-plate.
The Granatenwerfer was designed to be used in two modes, high angle and flat trajectory firing. Flat trajectory firing was used for the destruction of light cover such as sandbag revetments and loophole plates. In some instances it was used against sentry posts when the situation was favorable. The accuracy of the weapon was reduced when it was used in a flat trajectory manner as opposed to high angle fire. High trajectory fire was used against targets that were out of the line of sight, sap heads, trench works, infantry in trenches and in order to assist raiding parties or patrols while in No Man’s Land.
The men trained to use the ‘Granatenwerfer’ were given constant practice in order to be able to accurately judge the distance to their target. This prevented the need for fire registration. If the fire registration were protracted then the enemy would be able to seek cover or evacuate the position being targeted.
There were three methods of fire employed by the “Granatenwerfer’:
A. Independent fire. For flat trajectory fire against light cover.
B. Salvoes. For high angle fire for effect when carried out by a battery of ‘granatenwerfers’ against targets behind cover.
C. Barrage fire. Rapid high angle fire at ranges suitable for barrage purposes.
The factor of surprise largely contributed to the success of fire for effect, including moral effect. The most advantageous target to engage was usually the enemy’s infantry in a trench. In order to be effective against the enemy infantry and more especially to prevent any movement to a flank a wide front must be bombed simultaneously. In order to achieve this the ‘Granatenwerfers’ would normally be employed in batteries.
The most convenient number of ‘Granatenwerfers’ to group in a battery was four. If a larger number was used the commander of the battery could not maintain control by means of verbal orders, and it would take too long to personally check on each “Granatenwerfer’ before firing a salvo.
At least eight battery positions were to be prepared in each company sector for the ‘granatenwerfers’. The weapons were to be spaced at 20 yard intervals so that two of them could not be put out of action by one round from an enemy gun. The non-commissioned officers in charge of the ‘granatenwerfer’ was given instructions by the battery commander in regards to their targets, giving ranges and the necessary corrections for wind and drift. Then the order to prepare to fire was given.
In order to achieve the full effect of their fire all ‘granatenwerfers’ in a battery should be fired simultaneously. To insure this the order to fire would not be given until all of the non-commissioned officers in charge of their weapons reported that they were ready. Depending upon the direction of the wind or proximity of the enemy the order to fire could be given by word of command, by whistle or by a sign. However it was imperative that there was no possibility of alarming the enemy before the salvo was fired. The battery commander would normally position himself in the center of the battery.
The ‘Granatenwerfer’s’ high rate of fire and accuracy made it an ideal weapon to use in conjunction with offensive patrols designed to break into the enemy lines where it could be used to block access to the area under attack by the raiding party. It was also useful in driving off enemy patrols that had been detected in No Man’s Land.
Sorry about the chart, it did not come through properly