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Italian armor-piercing ammunition (Perforanti, Effetto Pronto, and EP Speciale)


Staff member
Posted 02 August 2009 - 12:13 PM by Alan Hume

I must be slacking as I just read about the EPS "Effetto Pronto Speciale" round today

it appears to be the italian equivelant of a HESH round

it seems from reading Comando Supremo and elsewhere that only the 47/32 gun and the Semovente 75/18 get this round (did the Semovente 47/32 get it too?)

I dont suppose anyone has any information on this round and where it was employed at all?

Posted 02 August 2009 - 01:18 PM by jwsleser


The following is from Cappellano appendice 13 (pages 295-200).

The following list are the weapons issued the E.P. rounds, the unit of fire (UNFOC)(quality) per gun and the percetage of E.P. carried in the basic load.

47/32 UNFOC - 250 - 1/3 ordonarie (HE), 1/3 perforanti (AP), 1/3 E.P.
65/17 UNFOC - 250 - 2/3 ordonarie, 1/3 E.P.
75/13 e 75/18-34 UNFOC - 250 - 9/10 ordonarie, 1/10 E.P.
75/18-35 UNFOC - 250 - 1/3 ordonarie, 1/3 perforanti, 1/4 E.P.
75/18 UNFOC - 250 - 3/4 ordonarie, 1/4 E.P.
75/27-06. 11 e 12 UNFOC - 250 - 3/4 ordonarie, 1/4 E.P.
75/32 UNFOC - 250 - 1/3 granate (shrap), 1/3 perforanti, 1/3 E.P.
100/17 mod. 14 e 16 UNFOC - 250 - 1/2 ordonarie, 1/4 E.P. 1/4 a d.e.

There are some notes I need to translate, but I have to attend church. I will get back to this later today.



Posted 02 August 2009 - 01:39 PM by JeffreyF

I think you are on Italianisti but if not go there and check archives as I guess you have already looked here. I will try to go off memory and apologies if this needs to be corrected.

There are 2 generations of HEAT round at least. EP, EPS and EP42 which may just be EPS. Basically Italian HEAT shell and then Italian HEAT shell with German nose fuse that helped increase angle at which proper jet would form and focus the projectile properly.

EP is the home grown Italian variety of HEAT shell. I think part of the HESH issue is that the EP round, iirc, used a base fuse. The nose of the EP shells from what I have seen in the US tech manual on French/Italian ordnance look overly rounded compared to a traditional shell. In addition standard Italian artillery practice for anti-tank fire was take an HE round and arm only the base fuse so as attempt to increase lethality against tanks when forced to fire HE at tanks. So either an HE shell with a delay base fuse or a poorly formed jet from an EP shell will probably make an observer wonder about what sort of shell was thrown at the tank?

check the description of studies on EP rounds versus captured tanks in North Africa in something like google groups(only seen it in Italian language afaik) it makes it sound this way the Italian EP round did not form a tightly focused slug of metal to punch through the armor. Although in this description it talks about an EP shell of 20mm for the Solothurn at rifle going through both sides of a turret on an captured M2 tank, which I have never heard of being used in combat? I'm a bit sleep deprived so probably just a good laugh at my not remembering the proper tank. It's been some years however I recall the description saying the armor plate was boiled away on a cruiser tank. However there were further tests done in Poland(?) against Soviet tanks and I believe the EPS shell in 100mm rounds was capable of defeating the armor on the turret side of an IS-2 which is 90mm at a 60 degree angle.

Apologies if this leads you astray.

Posted 02 August 2009 - 06:39 PM by jwsleser

First, a small correction. I mixed the terms unit of fire (UNFOC) and basic load in my earlier post. UNFOC is a logistical planning factor that normally indicates the anticipated number of rounds a single example of a type of weapon will fire in a day. If a 75/27 has a UNFOC of 250, this means the army staff is anticipating 250 rounds will be fired by one weapon in one day. It is a planning factor to estimate how much ammunition you have for combat.

Basic load is how many rounds a unit carries with it without any support. A basic load of 200 rounds of 47/32 in the Ariete Armored Division means that the division’s vehicles (tanks, limbers, and supply trucks together) have 200 rounds of 47/32 ammunition for every 47/32 gun in the division. A basic load of 60 rounds for a c.c. battery means that the limbers and any trucks organic to the battery carry 60 rounds per gun assigned to the battery.

To recap, UNFOC is planned/expected consumption over time (normally a day). Basic load is the ability to move (carry) by unit. A UNFOC is normally carried by several echelons of supply vehicles (or more likely stored in dumps). I should not have used both terms in the same sentence.

I will need time to read each gun entry in Cappelano to see when EP and EPS was available. I.e. EP was available for the 100/17 in mid 1942 (June/July), while EPS was available in May 1943. 47/32 EP was available to tank and c.c. units in A.S., and to the artillery units under the command of the 8th Army (in Russia) at the beginning of 1942 (Jan/Feb). By 1 May 1942, there were 12,537 of the 47/32 EP rounds in A.S. For the 75/27 series, EP, EPS and EP M42 were available. By June 1942, both the 75/27 series and the 75/18 for semoventi had 4 UNFOC of ammunition that included EP in A.S.

There is more data (including a lot of technical data on penetration) that will take time to work through. However, there are some other projects I need to get done at this time.



Posted 02 August 2009 - 10:30 PM by Dili

EPS appears in 43 and it is an evolution of EP.

Posted 11 August 2009 - 12:14 PM by Alan Hume

Hey Jeff

sorry to be a pain again, but I just wanted to ask your opinion

currently I am just going to put a blanket issue date of - available from 1942
on all EP Rounds for all guns

do you reckon this is okay or am I just fudging the issue too much?

Posted 12 August 2009 - 12:50 AM by Dili

65mm i have APR42 and a "?"
75mm i have late 41 but most rounds went initially for Semovente 75/18 so 42 is okay
100mm JUL42
105mm MAR43
all above EP not EPS

Posted 12 August 2009 - 01:20 PM by jwsleser


I basically agree with Dili. I feel 42 is okay for the major AT systems.

None of the A.A. systems were issued AT/EP rounds as part of their unit of fire. I need to check each individual weapn to see if a A.T. type round was developed. What I an reading supports that AA weapons had to use their standard AA round against vehicles if pressed to defend themselves.



Posted 13 August 2009 - 01:43 AM by Dili



Posted 13 August 2009 - 12:03 PM by Alan Hume


sorry but I'm actually thrown here,

65mm i have APR42 and a "?"
75mm i have late 41 but most rounds went initially for Semovente 75/18 so 42 is okay
100mm JUL42
105mm MAR43
all above EP not EPS

Dili, do you mean by this list that those guns didnt get EPS?

Did anyone get EPS?

Posted 15 February 2010 - 12:30 PM by david

Reading the above, can we confirm that the first deliveries of EP suitable for the 75/18 Semovente in N.A were in June 1942?
Or earlier?

Posted 16 February 2010 - 12:13 AM by Dili

I have late 41, but no source listed.

Posted 04 May 2015 - 09:56 AM by david

Guys, was there any EP ammunition for the 77/28?

Are there any tables here on this site, or the internet that give detailed penetration figures comparing EP to standard AP?


Posted 16 June 2015 - 12:22 AM by Dili

I don't think so.

Detailed data about penetration of EP rounds. I would also like to know the Italian tests with them, but i only saw what i call "guesses" based on assumptions.

Posted 04 October 2015 - 08:40 AM by david

Has anyone got any information of any quality about the penetration capabilities of 47mm, 65mm & 75mm EP please.

The rest is missing


Staff member
Ahh, I finally rediscovered where this question was asked.

Filippo Cappellano Le artiglierie del Regio Esercito nella seconda guerra mondiale Alberelli Edizioni Speciali, Parma 1998

Sorry for taking so long; I forgot where I had read this question.


Staff member
While searching for something else, I stumbled upon this info.

Originally posted in AHF by Andreas.

The power of the 75 and 100mm guns against armour was multiplied by the use of shaped charge projectiles
Experience shooting P.E. projectiles [these are Effetto Pronto (E.P. - HESH type rounds)] of 75mm and 100mm calibre as well as using the Solothurn at Saunnu (North Africa) against the side of a Mark VI tank at a range of 500m. Results were that a single shot from the 75mm removed a half meter square section of the 30mm armour of the vehicle shot at.
A 75mm shell hitting the 2 joint of two plates 30mm and 20mm thick respectively on the front of the hull opened the metal and curled back the metal tearing the upper inclined plate making a hole 30 x 50cm.
A 100mm shell hitting the front of the turret made from 2 x 20mm plates (40mm total) tore the face off the turret
A second shot at the turret tore it off leaving it on the ground
Conclusion of tests was that P.E. shells were more effective than normal shells
- Source for that test is 'Materiali in allestimento presso il 12 Autogruppamento' - NARA T821 roll 250

and this

In March 1942, in the Saunnu (Cyrenaica) area, the 12th
Autoraggruppamento (the Italian "experimental" unit in North Africa)
put the EP rounds for the WWI vintage 75/27 field gun and 100/17
howitzer to the test. Two 75mm and two 100mm EP rounds were shot at a
captured Crusader MkVI tank at a distance of 550 yards. The 75mm
rounds easily smashed and penetrated the side and frontal armor
plates, with plate shrivelling (presumably due to the "boiling jet"
effect). The 100mm rounds disintegrated the frontal armor and popped
the turret out of the tank.

The overall effect of the rounds was described as being decidedly
superior to that of the regular AP shots for those calibers.
Considering the obsolescence of the 75/27 and the 100/17 guns, it was
a remarkable upgrade. Such EP rounds should be quite effective even
against Grants and Shermans. Of course there were too few EP rounds


Staff member
I found this description of the use of EP in Russia. Originally poste on Feldgrau net by Tigre

"Serafimovich, July 30 to August 13, 1942.

The Battle of the sunflowers.

On July 30, 1942, began the joint efforts with the IR 578 (reinforced by the III. / AR 305) and the 6th Bersaglieri Regiment supported by four artillery groups I (100/17) and II/120 º ( 75/27); II/201 º (75/32) and LXII/30 (105/32) and anti-tank battery of 75/97/38 of 120 º was commissioned to begin offensive operations against the Soviet troops which occupied the bridgehead in the area of Serafimovich because it threatened the German southern flank.

At 03:00 hours began the advance in order to attack the heights before Baskovski. At the same time the Soviet units, hoping to surprise the Italian division while it was deploying, launched a powerful attack with tanks T-34 and BT-reinforced with infantry. At the end of the action 14 out of 39 armored vehicles were lying on the ground.

The tanks appeared around 13:30 hours at about 1000 meters from the anti-tank battery which started the shooting at 800 meters with 30 hollow-charge grenades and 30 high explosive, immobilizing the T-34 N º 78 and BT-7 No. 315 . Three cars went on to the attack and the battery fired another 20 hollow charge shells from about 300 meters, the T-34 N º 76 was immobilized with the second hit. The others two armored turned left and fled away; ten others grenades were fired from about 600 meters without result. Half an hour later suddenly emerged two T-34 and attacked the center of the battery with cannon and machine gun fire, the first was stopped some 8 feet away of piece 2 by a barrage of 10 hollow charge shells, one of them hit next to the gun turret, killing the entire crew. The second, T-34 No. 77, received 8 hollow charge grenades, one of them struck on the left side of the turret immobilizing it.

Legione Croata Autotransportabile http://www.battlefront.co.nz/Article.asp?SectionID=2
IL BERSAGLIERE DEL 6° REGGIMENTO http://nuke.gmtmodellismo.it/Default.aspx
LA CAVALLERIA ITALIANA IN RUSSIA: SCIABOLE CONTRO MITRAGLIATRICI http://www.storiain.net/arret/ http://groups.yahoo.com/group/italianis ...artic6.asp

La Milizia Volontaria Sicurezza Nazionale. La Campagna di Russia 1941-1943 (*) http://www.regioesercito.it/index.htm
Die 305. Infanterie-Division. Hauck
BERSAGLIERI SUL DON. Umberto Salvatores."

Note the c.c. in question are the modified French 75mm guns (75/98 c.c.).


Staff member
And this by Wiking on alternatehistroy.com

They had different calibers, I think the HESH style one was 47mm with their AT gun. EP shells were HEAT rounds, but one variant, which I believe was for the 47mm AT gun, had a rear fuse, so the shaped plastic explosives 'squashed' against the armor before the rear fuse detonated and was basically a HESH round as a result. But that was only one of several types. The EP shell below was a weird design for HEAT and was the reason it resulted in a HESH projectile


The EP shell was a supposed to be a shaped charge, but due to the insensitivity of the base detonator the shaped charge flattened against the target before the base detonator contacted a hard surface and detonated, inadvertently creating a HESH effect even though it wasn't designed to do so. It ended up being MORE effective than the HEAT of that caliber as a result. Meanwhile the EPS had a nose fuse that detonated the shaped charge properly, so it functioned as designed as a HEAT round. The HESH effect was totally unintended with the EP shell and was 'fixed' with the EPS nose fuse. So what I'm suggesting to get the early HESH principle noted by both the Brits and Axis powers is that the 'malfunctioning' EP shell actually is a totally different effect and they exploit it. The Italians and Germans notice it in the Desert in 1940-41, while the Brits find out about the HESH effect by testing captured Italian EP rounds. So both sides then develop the concept starting in 1941 as a POD. So say by 1942 both the Brits and Germans are fielding the HESH round, which then the US starts fielding in 1943. Perhaps then via LL the Soviets get it in 1944, as they lacked a lot of domestic plastic explosive production capacity due to the invasion disrupting their explosives output (IOTL LL provided a lot of their explosives and they didn't field their own HEAT rounds I think for the same reason, they lacked the necessary plastic explosive output to make the shaped charge; I do know that for sabotage purposes they fielded a lot of US plastic explosives, British output of plastic explosives was lower than Germany and the US had the highest output of anyone during the war).


New Member
WoW that is very help full TY, whats interesting to note is the reference to the use of these shells in 1940, also that the 47mm EP shell would seam to quiet effective do to it's HESH characteristics apparently, presumably this is why they were used or issued to the extant they were, providing for better effect at range possibly over the standard AP round ?

Curious in at that there is no mention of the 65/17


New Member
I keep thinking of all the ordance and weapons that were captured at different times by the British and given the use of even captured Italian Arty they must of inventoried those stocks, would not these inventory's serve as an indicator for the EP's rounds entry date or at least sugest a more accurate time frame ?


Staff member
From another thread on the old CS (Anti Tank Performance).

Neil Wakefield Posted 28 August 2003 - 03:08 PM

Data on the armour penetration capabilities of Italian artillery is hard to come by. I've found another site (http://miniatures.de...nt/shellsI.html) which provides armour penetration details for quite a few weapons at 100m against vertical armour. However I've been warned about the accuracy of the information on this site. For example it says the Italians had a HEAT round ('Effeto Pronto') for the 65/17 Infantry Gun which could penetrate 120mm of vertical armour at 100m. Since a short German 75mm gun only penetrates 100mm at the same distance I'm suspicious.
Any data on the armour penetration capabilities of Italian anti tank guns, tank guns, anti aircraft guns, field and medium artillery or other web sites/books where I could find the data would be appreciated.

Attilio Posted 30 August 2003 - 07:59 AM

You can find a lot of data on the good book of Cappellano:
Le artiglierie del Regio Esercito nella II guerra mondiale. Parma 1998, Albertelli ed.

It's very difficult find data on the AT capability of EP (effetto pronto)round. Pignato in a book about the medium italian tanks reported 70 mm for the EP round of 75/18 gun mounted on the self propelled gun. There are no sure data on the AT capability of 65/17 gun.

Best regards

Daveh Posted 30 August 2003 - 04:31 PM

The data below is copied from
World War Two Armour Penetration Statistics by John Salt (formatted by Valeriy Potapov)

"Anti-Tank Weapons" Peter Chamberlain and Terry Gander, MacDonald and Jane's, 1974.
It 37/45 400 yds 30º 38
It 47/32 M35 550 yds 0º 43

"The World War II Databook", John Ellis, Aurum, 1993, page 304. Ranges in yards, Ellis, 1993
Weapon Ammo 250 500 750 1000 1500 2000

It 20mm 29 24
It 37mm 32
It 47mm 48 (400) 38 32

"The Unknown Alamein", Charles Messenger, Ian Allan, 1982
range penetration
It 20mm Breda 500 24
It 47/32 1000 32

"Panzer Bait: With the 3rd Royal Tank Regiment 1940-1944", William Moore, Leo Cooper, 1991

Weapon Ammunition Range Penetration
It 47mm in M13, M14 400 48

Pages 186-187 of an unknown small-format (8 × 5½ inches) hardback
Weapon Ammunition Range Penetration
It 47/32 Model 37 AP 1000 26
It 90/53 AA gun AP 1000 101

"Tank Armament in World War Two", Paul Woodman, in: Airfix Magazine, Vol. 3 No. 5, Alan W. Hall (publications) Ltd, August 1991, page 174.
Weapon Ammo 500 1000 1500 2000 metres
It 47mm APC 55 43

The data for the Cannone contracarro da 37/45 is widely available as this is the German Pak 35/36

Michi Posted 25 January 2004 - 07:12 AM

As my file doesn't work anymore, here are my informations about the difference of the 47mm L/32 and 47mm/L40 are as followed:

47mm L/32
Produced by Ansaldo.

Carro Armato Medio M13/40
Carro Armato Medio M14/41
Carro Armato Semovente Leggero L6/40 da 47/32
Auto Blinda AB 43 (not sure if 47mm L/32 or 47mm L/40)

Initial speed: 630 m/sec (or 610 m/sec)
Penetration: 40mm @ 650m at 30°; 32mm @ 1000m (or 26mm @ 1000m)
Max. effective range: 1.600 metres
Rate of fire: 12-14 rounds per minute
Weight of perforating shell: 1,5 Kg.

47mm L/40
Produced by Ansaldo.

Carro Armato Medio M15/42
Carro Armato Semovente Leggero L6/40 da 47/40 (very late production models) (not prooved yet)
Auto Blinda AB 43 (not sure if 47mm L/32 or 47mm L/40)

Initial speed: 900 m/sec (or 750 m/sec) (or 829m/sec)
Penetration: 57mm @ 500m; 43mm @ 1000m
Other datas as the 47/32 gun

MfG Michi

nmao Posted 13 May 2014 - 03:48 PM


Just to add someting to this old thread

It seems the first 200 EP 75mm rounds were available in November 1941.


Post by Attilio60
Nel già citato articolo sulla battaglia di Bir El Gobi pubblicato
sull'ultimo numero di Storia Militare l'autore afferma che alla
italiana vennero consegnate in tale occasione 200 granate Effetto Pronto di
calibro 75 mm.
La fonte di questa informazione e' il diario storico del comando divisione
dell'Ariete, che alla data del 12 novembre recita:
"Vengono assegnati n.200 proiettili da 75/27 ad effetto E.P."
Post by Attilio60
Nelle mie fonti la distribuzione di tali munizioni in Africa Settentrionale
avvenne solo dopo i primi mesi del 1942.
Le tue fonti (quali sono?) probabilmente non sbagliano di molto: mentre
in novembre fu consegnato un numero non elavato (200) di proiettili a
un'unita' d'elite come l'Ariete, probabilmente solo nell'anno successivo
(con l'arrivo dei nuovi convogli) la diffusione avvenne in modo piu'
capillare e in quantita' considerevoli.



Dili Posted 13 May 2014 - 10:33 PM

I have this for EP rounds. Not necessarily Africa.

65/17 : EP round available in Spring 42
75/27( and 75/18 for Semovente) : late 41
100/17 :second half 42, EPS in May43
105/28: the round was called mod.43 so i suppose it arrived in 1943.
47/32: i have not the data handy since it was a useless technology due to small caliber projectile.

David Posted 15 May 2014 - 05:23 AM

Do we know in what sort of numbers each type was available in Africa and when (apart from the 200 listed above).

Then some comparative penetration figures would also be useful.

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Staff member
I keep thinking of all the ordance and weapons that were captured at different times by the British and given the use of even captured Italian Arty they must of inventoried those stocks, would not these inventory's serve as an indicator for the EP's rounds entry date or at least sugest a more accurate time frame ?

If that information was recorded and if you can find those records, possibly yes.


WoW that is very help full TY, whats interesting to note is the reference to the use of these shells in 1940, also that the 47mm EP shell would seam to quiet effective do to it's HESH characteristics apparently, presumably this is why they were used or issued to the extant they were, providing for better effect at range possibly over the standard AP round ?

Curious in at that there is no mention of the 65/17

1- where? this: "...The Italians and Germans notice it in the Desert in 1940-41...." that is not a reliable source.

2- why? HESH effect is based on amount of explosive. 47mm had a tiny amount. There is no way that 47mm HEAT or HESH could be an effective round.
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Staff member
To be clear, EP functions as a HESH round as it uses base fuzing. EPS functions as a HEAT round as it has standoff and point fuzing.

RE: 47/32. Cappellano states on p. 254 that on 30 April 1942 there was in A.S.: 12.537 EP rounds, 48.370 ordinary (HE), and 84.870 PP. So ~ 8.6% of the 47/32 rounds in A.S. was EP in April 1942. In 1943 a circular was issued stating that the E.P. should be used like an ordinary round and not used as c.c.

The mod. 39 PP round could penetrate 40mm angled at 60º at 650m. At 1600m it would penetrate 30mm at 30º. (Cappellano p. 255)


New Member
If this is suspect, and I am not saying it is but rather asking, why some many sources seam to suggest a higher penetration value for the EP rounds than would seam reasonable, part of this I think is that contemporary principles don't seam to work well to judge the ww2 ere HEAT or HESH rounds by and that the way these figurers were arrived at in the first place is probably based on inconsistency's in test methods and materials employed at the time


Even if the 47mm EP round could only do 40mm it would still be effective if used at range in that it would provide better penetration, and against lighter targets it would be effective because of the nature of the Shell, that is sometime just punching holes in a target is not as good as showering the interior with an explosive blast of material, the tables below are for AP rounds and are offered up as means to effect comparisons with the EP rounds, and to show that the EP rounds were not really necessary till later in the war, which is interesting if some sources are to be believed that as early as sometime in 40 they had EP rounds for the 47mm




Staff member
Again to be clear, there was no wide-scale availability/use of EP in 1941 for any weapon. We have reports that a small amount of EP was sent to A.S. in late 1941 for testing, but it isn't until the spring of 42 that EP was being produced and issued in any quantity. June 42 in A.S., there was only 4 UNFOC for 75mm field guns (of which 250 rounds per gun would be EP) and 2 UNFOC for the semoventi (of which 125 rounds per gun would be EP) in the entire theater. I have posted the data for the 47/32 above.

As for the different penetration values, without knowing the source it is difficult to understand what the numbers are saying. Cappellano give the following penetration data for the 75/18 PP (35mm at range of 500m at 30º, 30mm at 1000m at 30º) which is less than your chart data. I have already posted the 47/32 PP data from Cappellano which is less than the value show on the chart you posted.


Staff member
The following are reports quoted in Cappellano's Le artiglierie del Regio Esercito nella seconda guerra mondiale.

Letter 24 November 1940 from the G.M. Ispettorato Superiore Servizi Tecnici. (p. 70)

The 75/34 cannon mod .37 for its power, the low silhouette, the wide field of horizontal shooting has interesting possibilities of use against tanks. It is assumed that with a good piercing projectile, it can pierce 50-55mm thick armor while the 47/32 cannon, which is currently our most powerful anti-tank gun, will not penetrate armor thicker than 35mm, and will therefore come in a state of crisis in the face of the powerful armored tanks that are in production for England. So I ask the Stato Maggiore to examine the opportunity to proceed with the production of the 75/34 mod. 37 on a larger scale than currently planned.

The firing exercise against Kw-1 and T34 tanks with the cast steel type turret and the rolled steel turret that took place at the [firing] range of Deba in Poland in October 1942. On the Italian side, the shells were the 75mm EP and 100mm EP with Gnutti fuzes (for the 100mm 2 types, one with a short nose in Zama alloy and one with long nose in duralumin).

Our 75mm EP projectile proved that it could not produce effects against the T34 tanks, while the corresponding grenade (German n.d.r.) HL definitely exceeded it. In fact, while the 75 EP (which despite impressive destruction effects on plates with a thickness of 30mm) had limited efficiency against the plates of the T34 tank with a thickness of 40mm and 45mm, the HL of the same calibers penetrated, at 42º plates of 40mm of laminated steel, and at 49º that of 60mm of cast steel plates. (p. 90)

Our 100mm EP projectiles, on the other hand, have shown that they can produce, on the same T34 tanks, very serious destruction effects, at least comparable to those obtained from the German 105 which also contains about 500 gr. more explosive, and in any case with secondary effects certainly more conspicuous, even when there wasn’t interior detachment. Also on the turret of the Kw-1 wagon (75mm thickness of rolled steel), with an impact angle of 75°, serious injuries were obtained with large interior detachment, and - in one case - also a through penetration of 10x2 mm. These results have surprised the German technicians, some of which have not ruled out that any effects of the putting the tanks out of action, the primary and secondary effects obtainable with our grenade EP may be more useful, than the simple melting perforation achievable with the HL grenade. (P. 96)


Staff member
I don't know. This is all Cappellano quoted from those reports.



It is interesting the significant effects of 100mm vs 75mm EP points to a scaling factor.

the 100mm gun can deal with a 75mm plate 75º but the 75mm gun is unable to deal with a 40-45mm (what angle 45º ? seeing the tests with HL German round 42º and 49º?) and can only do it to 30mm albeit there with good destructive power. Points also to an abrupt loss of effectiveness.

On another hand:
75mm at 75º is 78mm relative thickness (0.78:1 round diameter vs penetration ratio with success), 40mm at 45º is 57mm (0.76:1 ratio with failure so it is worse) , this is the best case scenario for 75/18 mm gun. These are numbers that are inferior to what is usually said that EP are capable of, disregarding the obvious unrealistic numbers sometimes posted, credible numbers are said to be around 0.9 :1.


One reason that would be great to have the test report.


Staff member
Just to document, the 1938-1939 Italian manuals on artillery state that proietto perforante (PP) was issued for the 65/17 and the 75/27. Unfortunately, no penetration data is provided.