Requesting a non-tech answer please -

[Bardess]

What is the main difference between shrapnel shells and percussion shells?

[jay dubaya]

Hi Diane,

a shapnel shell is timed to explode whereas a percusion shell would explode on impact

[Tom Morgan]

Shrapnel shells are filled with small metal balls (usually lead) and they are designed to burst in the air via a time-fuse, rather than when they hit something via a percussion fuse.

Percussion-type fuses were used with high explosive shells. There were several types but basically they set off the explosive in the shell when the shell hit something, or if there was a sudden change in direction, such as when a shell grazed off the ground.

A shrapnel fuse sends out an explosive flash after a preset time and a simple tube inside the shell transmits the flash down to a second explosive charge which pushes out the balls. These are already travelling at the same speed and direction as the shell, of course. The result is a spray of shrapnel balls.

Tom

[Bardess]

Thanks for the explanations. I understood 'shrapnel' but didn't realise that they burst in mid air. Cheers

[Rockdoc]

Diane, it's the fuze you're really asking about. The type of shell doesn't make an intrinsic difference but the way that you want to use the shell does. Shrapnel and HE shells were used in AA gunnery, using time fuzes, and even when you have a fuze that is triggered by contact it doesn't have to mean that it goes off immediately. Heavy shells needed to bury themselves before exploding to damage deep dug-outs, for example, so there would have been a short delay included.

Keith

[Bardess]

Thanks Keith. Before posing the question I performed a search for percussion and the results all mentioned fuzes but no explanation was offered. I wanted to know why 2 types of shells were being used at the same time basically. Early Jan 1915 by R Warwickshire R.

[truthergw]

Essentially, a shrapnel shell was anti-personnel whereas percussion was used to explode a high explosive. A shrapnel shell was to all intents and purposes like a giant shotgun flying through the air, which fired its contents at the target. A very effective weapon against men and horses when the fuze was set correctly and was very nearly all there was available at the start of the war. There was a great demand for high explosive which was not met until the Somme. The percussion fuze set off the high explosive on contact and was essential to smash trenchworks , barricades and destroy guns.

[kenf48]

and whatever you do don't confuse the lethal jagged pieces of shell casing, from either projectile, with 'shrapnel'!

So much for non-tech

Ken

[Rockdoc]

The nose comes off a Shrapnel shell as the explosive charge, which is at the base of the shell, pushes against a piston to force the balls (aka bullets) out. They have to be triggered before landing to have any effect and getting a consistent, optimum height was difficult because the timing system in the fuzes was based on the rate of burning of a ring of powder that was initiated by the acceleration of the shell up the barrel. The length of the delay was adjusted by moving part of the fuze, during setting, and that changed the length of the powder to be burned before the flame front communicated with the detonating charge.

To damage surface structures you would fire HE with a fuze that detonated immediately on impact, known as a graze fuze. To destroy bunkers and other underground structures you would use a fuze that was triggered on impact but which also had a delay incorporated so that the shell exploded deep in the earth. Shrapnel was used to damage barbed-wire entanglements, with varying degrees of success, and as an anti-personnel weapon. It was all the 13- and 18-pdr guns had available at the start of the War because it had been expected that they would support the troops in open, mobile warfare, where they would fire over open sights (i.e. directly) at approaching enemy soldiers. It was a killer but could do little damage to a structure. It's very much a case of horses for courses.

By the way, it would be wrong to think that both types were being fired by the same guns. In early 1915 there would have been no HE for 13- and 18-pounders so any HE recorded was being sent over by the Heavies. I'm pretty sure that the Heavies never fired Shrapnel.

Hope this helps,

Keith

[calibre792x57.y]

The nose comes off a Shrapnel shell as the explosive charge, which is at the base of the shell, pushes against a piston to force the balls (aka bullets) out. They have to be triggered before landing to have any effect and getting a consistent, optimum height was difficult because the timing system in the fuzes was based on the rate of burning of a ring of powder that was initiated by the acceleration of the shell up the barrel. The length of the delay was adjusted by moving part of the fuze, during setting, and that changed the length of the powder to be burned before the flame front communicated with the detonating charge.

To damage surface structures you would fire HE with a fuze that detonated immediately on impact, known as a graze fuze. To destroy bunkers and other underground structures you would use a fuze that was triggered on impact but which also had a delay incorporated so that the shell exploded deep in the earth. Shrapnel was used to damage barbed-wire entanglements, with varying degrees of success, and as an anti-personnel weapon. It was all the 13- and 18-pdr guns had available at the start of the War because it had been expected that they would support the troops in open, mobile warfare, where they would fire over open sights (i.e. directly) at approaching enemy soldiers. It was a killer but could do little damage to a structure. It's very much a case of horses for courses.

By the way, it would be wrong to think that both types were being fired by the same guns. In early 1915 there would have been no HE for 13- and 18-pounders so any HE recorded was being sent over by the Heavies. I'm pretty sure that the Heavies never fired Shrapnel.

Hope this helps,

Keith

Hi, Keith. I recall reading an account of HMS Queen Elizabeth opening fire from the straits on a Turkish attack coming over a knoll at Gallipoli with 15 inch naval rifles using shrapnel shell. The writer said they burst over the knoll and raised dense clouds of pink dust and when cleared there was no sign of any further movement. 15 inch shrapnel is pretty rare I would have thought, but there was plenty of sixty pounder shrapnel used. Additionally, I believe the first three rounds of 18 pdr H.E. were fired at the stableblock at Hooge by an 18 pdr brought forward into the line under cover of darkness. This was in October 1914. Cheers - S.W.

[jay dubaya]

'Barking Kate' the 6" BL Mk 19 Field Gun was used to lob 100lb of shrapnel

[Rockdoc]

Mea culpa! It's true that HE was fired at Hooge in October 1914 but these were shells sent for evaluation and testing, not for use against the enemy. A few HE shells were used during 1st Ypres but the History of the Ministry of Munitions Vol X says that the uptake was very slow and some Brigade Commanders actually distrusted it, following early problems and accidents. There was a major shortage of shells at this time and French warned London that he might have to minimise artillery support unless things improved rapidly. Field gun Shrapnel production was established while HE was being developed. On that basis, I'd still argue that the likelihood is that the field guns were firing Shrapnel and the Heavies were firing the HE.

Keith

[centurion]

Hi, Keith. I recall reading an account of HMS Queen Elizabeth opening fire from the straits on a Turkish attack coming over a knoll at Gallipoli with 15 inch naval rifles using shrapnel shell.

I'm surprised that there was any as it would be useless in any naval engagement.

[Bardess]

Good morning. Yes, I did realise that shrapnel balls and fragments were different beasts and I now know why 2 types of shells were sent over and what/who they were aimed at. Thanks for all the info guys. The mist is lifting ...

[Piorun]

So much for your "non-tech answers", Diane The lads have given you great info, tho'. Antony

[nigelfe]

A few corrections and clarifications.

Shells could have different fillings, host notable shrapnel bullets or High Explosive, but there were others in WW1 (and since) notably chemical (usually called 'gas', which it wasn't, although you might use 'gas' to describe the product of evaporating liquid delivered by a bursting shell).

Shells have fuzes, usually at their nose, but there were some base fuzes. These fuzes have one or more means of fuctioning, sometimes selected before firing, others happening as a failfunction mode.

Shrapnel mostly burst in the air, this meant the fuze had a timer, set to something less that the time of flight to impact. Airburst, normally called time, fuzes could have one of two types of mechansim, the obvious is clockwork, used by the Germans but hardly, if at all, by UK. The other was 'powder burning' AKA igniferous, which used a burning length gunpowder in a tube in the fuze.

Percussion fuzes were of two types in WW1, first was 'direct action' (DA) when the fuze functioned immediately on impact, basically the nose had a firing pin in it and this was hit back onto a detonator on impact. Second was 'graze', this normally started by the shell being suddenly slowed down as it penetrated something, this caused a slight delayed between the nose first touching the ground, etc, and the moment the fuze actioned the shell. Base fuzes were usually graze action.

However, some fuzes used with shrapnel also had a graze action, which meant the fuze actioned to bust/release the payload a fraction of a second after impact. Before WW1 this was favoured for use against enemy artillery to penetrate the gun shields.

I don't think delay fuzes were used by UK in WW1, these were like DA fuzes but with a delay device added between the nose firing pin and the detonator.

[Pete1052]

There are a lot of shrapnel balls on the ground at Fort Sill, Oklahoma, where I once attended various Field Artillery schools. I believe they were mainly from the French 75s we used to have. There are also a lot of jagged shell fragments on the ground there as well.

For about 70 years journalists have tended to use the word shrapnel to describe shell fragments, to the extent that people now think you're nit-picking if you try to correct them. The same thing goes on when chemical weapons are said to be gas, the old term.

[Bardess]

Thanks nigelfe but your post has slipped quietly over my head and landed a million miles away.

Pete, I have to say that the word 'shrapnel' normally conjures up red-hot fragments of razor-sharp metal - but not any more

[Pighills]

Well, I have learned all about shrapnel too! It's amazing how these 'myths' come about. Thanks for posting an interesting question, and thanks for the comprehensive replies too, pitched perfectly!

[Rockdoc]

Calling shell fragments Shrapnel isn't only caused by ignorance of military matters. My Grandfather was hit by fragments from a counter-battery shell and some of the smaller bits were left in by the doctors. When asked about the blue marks on his face he always referred to them as Shrapnel.

Keith

[MikB]

...I have to say that the word 'shrapnel' normally conjures up red-hot fragments of razor-sharp metal - but not any more

The term usually used by naval writers is 'splinters' when referring to bits of the shell body flying about. To me, this seems suitably jagged and unpleasant as a replacement for 'shrapnel' in this context.

Regards,

MikB

[Piorun]

Calling shell fragments Shrapnel isn't only caused by ignorance of military matters. My Grandfather was hit by fragments from a counter-battery shell and some of the smaller bits were left in by the doctors. When asked about the blue marks on his face he always referred to them as Shrapnel.

Keith

I'm with you, Keith. The lads on the ground didn't really care whether it was a shell fragment or a shrapnel ball. If it was a shrapnel shell, they tended to just call it shrapnel, no matter what bit of it took off what bit of them. In formal reports or histories, we see "a shell took his head off" or "a shell busrt nearby and a fragment took off his arm" but these were written after the fact. In a shrapnel attack, it was all shrapnel. Antony

[nigelfe]

The term usually used by naval writers is 'splinters' when referring to bits of the shell body flying about. To me, this seems suitably jagged and unpleasant as a replacement for 'shrapnel' in this context.

Some might prefer 'shards' on the grounds that its shorter and simpler, but I've seldom come across it being used. 'Splinters' is certainly widely used, but to me it conjures up the notion of something very small, fragments from a burst HE shell can be quite substantial, particularly in WW1 when for various reasons fragmentation was quite poor (ie far too high a proportion of big bits by modern standards).

Referring to fragments from a HE shell burst as 'shrapnel' is common nonsence, just as calling 'cartridge cases' 'shells' is. (And journalists calling all artillery 'heavy'.)

I guess you might argue that before WW1 almost all UK artillery shells were shrapnel so its understandable that anything coming from a shell became 'shrapnel' as far as the infantry were concerned, and maybe 'shrapnel' is more evocative hence its popularity, but its also unambiguous, 'fragments' can invite the question 'of what?' so you need two words not one. Perhaps there's someone with a grasp of military German and French that can tell us if common use in those languages differentiated them.

[nigelfe]

Thanks nigelfe but your post has slipped quietly over my head and landed a million miles away.

Pete, I have to say that the word 'shrapnel' normally conjures up red-hot fragments of razor-sharp metal - but not any more

I do technical if you really want to be confused, but you can't have real understanding of anything without some mental effort, I'm old fashioned on this one. If pictures/diagrams are your thing then there's some on the ammunition page of my web site http://nigelef.tripod.com/ammo.htm

[Bardess]

Nope, does nothing for me but I'm sure other members will lap it up. Thanks anyway