Cannone da 65/17 vs Cannone da 47/32

[Aw Vincent]

Which of these two guns is more powerful ?

[Sergei]

I don't know if you mean anti-tank or anti-personnel power, so I assume that you mean just their physical bulk, ie. which one does more damage when dropped from a B-17. The 65mm gun weighs the same as two 47mm guns, so that would be the answer.

I hope this helps!

[Erwin]

Since you are a Jr member I'll assume you are asking re explosive power. That would be the 65mm (larger shell) over the 45mm.

[Aw Vincent]

I don't know if you mean anti-tank or anti-personnel power, so I assume that you mean just their physical bulk, ie. which one does more damage when dropped from a B-17. The 65mm gun weighs the same as two 47mm guns, so that would be the answer.

I hope this helps!

I meant anti-tank power, so ?

P.S.

I have read that the Cannone da 65/17 was obsolete during the World War II, so the italians tried to change it with the 47/32, but I don't undersant why the 65/17 was obsolete and I don't know what were the differences. :confused:

[Sergei]

I meant anti-tank power, so ?

47mm, without a doubt. HEAT shells would be the only expection, there the bigger caliber helps.

[John Kettler]

Aw Vincent,

Welcome aboard!

The first is a mountain howitzer with a short barrel, low muzzle velocity, and , from what I can tell, no AP projectile at all. My Italian is awful, but I can tell where the ammunition is listed, and no Effetto Pronto (HEAT) or Effetto Pronto Speciale (Improved HEAT) appears.

http://www.regioesercito.it/armi/65-17.htm

This is somewhat confusing, in that the Wiki indicates it was an effective antitank weapon in North Africa. My suspicion is that this held true only in the early days, when the British tanks were A10s and Crusaders armed with the 2-pdr.

http://en.wikipedia.org/wiki/Cannone_da_65/17_modello_13

Here is a somewhat problematic discourse on the basic shell for the mountain gun.

http://translate.google.com/translate?hl=en&sl=it&u=http://www.guerrabianca.org/html/artiglieria2.htm&prev=/search%3Fq%3Dcannone%2Bda%2B65/17%26hl%3Den%26client%3Dsafari%26rls%3Den%26biw%3D1402%26bih%3D876%26prmd%3Dimvns&sa=X&ei=SB49UNPTBOy62gW3noHQDA&sqi=2&ved=0CF4Q7gEwCg

By contrast, the Canonee da 47/32 was a proper antitank gun, which also fired a useful HE projectile.

Two separate statements on the potency, circa May 1942 of this antitank gun.

"As recorded by Major G/B. Jarrett in May 1942: The German projectiles which have caused the greatest amount of damage to Allied tanks in the Western Desert campaigns have been the A. P. -H. E. type in 47 mm, 50 mm, 75 mm and 88 mm respectively. These projectiles at long ranges need only attain a partial penetration and the explosive charge can complete the destruction of at least the tank crew. At closer ranges the destructive effect is very great, where in many cases destruction of the tank is permanent."

"The Italian 47 mm armor-piercing round contained a high explosive filler with a delay fuze. Penetration of a British tank by a 47 mm Italian armor piercing shell frequently resulted in crew members being wounded as well as destruction of the tank by causing irreparable damage or by setting it on fire."

The Wiki confirms the weapon's dual role, but fails to note the AP is actually not shot, but is APHE.

http://en.wikipedia.org/wiki/Cannone_da_47/32_M35

So, until someone with better knowledge of the first weapon comes along, my answer is the Canone da 47/32. Hands down!

Here is a most useful guide to Italian artillery ammunition. Unfortunately, the only projectile shown for the mountain gun is straight HE.

http://www.scribd.com/doc/52183493/Handbook-of-Enemy-Ammunition-Pamphlet-7-UK-1943

Regards,

John Kettler

[Baneman]

Aw Vincent - in gun designations, usually the 1st figure refers to calibre and the 2nd figure ie. the 17 in 65/17, refers to barrel length. Also often written with an "L" eg. German PanzerIV tank gun is a 75L48.

Generally speaking, the longer the barrel, the greater the muzzle velocity and the better for Anti-Tank usage.

This is a generalisation, but is a useful rule-of-thumb

Don't write off shorter barrel guns though, but you have to then look at their ammunition - if they have HEAT ammunition ( a shaped charge which doesn't rely on kinetic energy to penetrate the armour ) then they can still be dangerous to tanks, but HEAT ammunition is often in short supply.

Hope this all helps.

[womble]

To elaborate a bit on Baneman's point, the "Length" number is usually the multiple of the calibres that would most nearly equal the barrel length. So a 75/43 has a barrel length of 43x75 ~ 3225mm where a 75L48 has a length of ~3600mm. Your 65/17 has a stubby barrel of ?1105mm, whereas the 47/32 has a slightly zoomier barrel length of ~1500mm

[Mitra76]

The "granata perforante" in the list is armour piercing; the 65mm was sufficient for stop 1940/41 english tanks a part the Matildas; it had less velocity than the 47/32 but the is heavier and with bigger expl.charge. The Effetto Pronto (HESH) and Effetto pronto speciale (HEAT) for the 47/32 start to be used late, so it was a necessity continue to use the 65mm

[Michael Emrys]

Aw Vincent - in gun designations, usually the 1st figure refers to calibre and the 2nd figure ie. the 17 in 65/17, refers to barrel length.

Just to add to the confusion, sometimes the second number refers to the year of adoption. This seems to be especially true in smaller armies such as the Italian.

Also often written with an "L" eg. German PanzerIV tank gun is a 75L48.

That's a more reliable designation for barrel length.

Michael

[John Kettler]

Mitra76,

Welcome aboard!

As you can see from the links I posted, the explanation I got in that one translation wasn't exactly accurate. It said "foil piercing" and seemingly was withdrawn in 1935. The explanation of the foil was even more confusing. Now, it makes sense, and the shell translation should be shell, piercing, which would've been immediately obvious. Really appreciate the clarification!

Judging from my research, the Italians had no HESH, and why people think so is detailed here. EP was crude Italian HEAT, and EPS had a vastly better German fuze and improved shell design.

This thread is terrific in that it also gives us the ammo split for the Canone da 65/17. One third of its combat load is EP! The chart provided by Mod Jeff Laser is a wonderful addition to the CM database, detailing EP and EPS allocations for a slew of weapons.

http://www.comandosupremo.com/forums/topic/5459-effetto-pronto-speciale/

The only World War II HESH I know of was the "Wallbuster" fired by the Churchill AVRE as the famous "Flying Dustbin" and the 7.2" Burney recoilless rifle.

http://en.wikipedia.org/wiki/High_explosive_squash_head

Regards,

John Kettler

[Kat Johnston]

I meant anti-tank power, so?

In game:

Either type of cannon works against the lighter armour and against infantry.

Neither can destroy a Sherman from the front, though if you get lucky you may immobilise the tank. The AT gun can sometimes beat Sherman side armour.

I'm bored. I'll do some testing.

[John Kettler]

John Johnston,

It occurred to me, after my last post here, that the Canone da 65/17 may have one advantage I didn't realize before. The relatively looping trajectory at longer ranges may, if modeled in the game, improve the effectiveness of whatever antitank round is being fired, in that such a trajectory might well offset at least some of the glacis slope effects for a Sherman. Contrariwise, this would not be helpful against vertical side armor. That said, I recall the Germans had major issues with their 75mm HEAT round, which reportedly was considered accurate to a whole 400 meters!

Regards,

John Kettler

[Sergei]

Just to add to the confusion, sometimes the second number refers to the year of adoption. This seems to be especially true in smaller armies such as the Italian.

Italian guns are not that hard to decipher, most of the time - M (Modello) signifies the year whether it's an artillery piece or a rifle. Eg. the cannon M35 was introduced in 1935, Breda M30 in 1930 etc. Tanks take a little break from this but are nevertheless logical, so M13/40 is a 13 ton tank introduced in 1940.

German guns were named in much less logical manner, eg. sFH 18 (15cm) was introduced to service in 1935, leIG 18 (7.5cm) entered production in 1932 etc. The US naming convention gives you just as little information - M1 could be a mortar or a howitzer or a million other things.

[John Kettler]

Sergei,

I would characterize the German nomenclature as a functional description, followed by the bore. Once you know the system, it's far more useful than either the Italian or the American one. sFH =schwere FeldHaubitze =heavy field howitzer; leIG=leichteI nfanterieGeschutz=light infantry gun. I do not understand what the "18" means and never have. Indeed, I have never thought about it before. Maybe it's a branch designator.

Regards,

John Kettler

[Andrew H.]

Some background info for the OP:

At the beginning of the war, most armies had two kinds of direct fire weapons: (1) small caliber, high speed guns for anti-tank purposes; and (2) high caliber, low speed guns for anti-personnel purposes. Early on, the US and the Germans used a high speed 37mm gun for AT purposes and a low speed 75mm gun for AP purposes; the French (and presumably the Italians) used a high speed 47 mm gun and a low speed 75mm gun. The British used a high speed 40mm AT gun (called a 2-pounder) and a low speed 3" howitzer (about 76mm).

As armor improved, the small caliber AT guns weren't powerful enough, so the combatants moved to higher speed large caliber guns for AT purposes: the US moved to the 75mm gun on the Sherman; the Germans to the long 75mm gun on the Pz IV and StuG; the British also had a longer 75mm gun. But the Italians weren't able to make this upgrade, so they are essentially fielding the pre-war models which are largely obsolete against modern tanks.

(Later on, even higher speed 75mm guns will be around, making the guns on the Sherman & Pz IV essentially medium speed guns.)

[Aw Vincent]

thanks for all !

[Mitra76]

Mitra76,

Welcome aboard!

As you can see from the links I posted, the explanation I got in that one translation wasn't exactly accurate. It said "foil piercing" and seemingly was withdrawn in 1935. The explanation of the foil was even more confusing. Now, it makes sense, and the shell translation should be shell, piercing, which would've been immediately obvious. Really appreciate the clarification!

My pleasure; the exact translation tells the ammunition type was introduced starting from the 1936; the ammunition withdrawns from the 1935 was the canister type (mitraglia). Probably the translator merge the lines.

Effetto pronto was not thought as a Hesh but at the end it worked like a HESH, because the distance reduced his efficiency, thing not possible for a true HEAT. The trigger of ammunition was in the back like in a AP warhead but with the form of a HEAT, so the explosion was caused after the full pressure of warhead over the hull (which having the form of a HEAT cannot penetrate), a true heat will create the explosion jet before the warhead was completly pressed, creating a single point of fusion in the hull.

The confusion is from the form of EP, extenally like a HEAT but inside like a AP. In reality also EPS are not fully HEAT because at the model 42 was considered a full HEAT. I don't know what this the difference between EPS and EPSmod42, perhaps a improvement in the design and warhead.

[John Kettler]

Mitra76,

Very much appreciate the detailed explanation! Am thinking BFC could've used you in CMFI the way it did Valera Potapov (www.iremember.ru) for Cmx1's CMBB. I think this EP/EPS/EP 42 issue needs further work, perhaps in the patch.

In one of the links I gave, the spec sheet in Italian for the 65/17, the mitraglia round was mentioned. I presumed, by its similarity to mitrailleuse, that it was canister, since shrapnel was listed elsewhere.

http://en.wikipedia.org/wiki/Mitrailleuse

Regards,

John Kettler

[John Kettler]

Mitra76,

That was, of course, until I feel headlong into that mire of a translation! Yet another lesson for me in going with my initial sense of things.

Regards,

John Kettler

[Kat Johnston]

I've lined up some Shermans and had them shot at for a bit with a range of Italian weaponry. Had some tanks at slightly different elevations to ensure they were hit all over.

At very close (200m) range, shooting until ammunition runs out or for up to ten minutes:

20mm ATR:

Frontally: is occasionally able to penetrate the lower front hull, but never does any significant damage.

At 45 degrees sidewards: can score partial penetrations on the upper side hull. Can result in mobility kills if its in a position to hit the wheels.

At 90 degrees side on: can penetrate the upper left hull and kill the tank given time.

20mm Breda autocannon:

Frontally: can occasionally penetrate the lower front hull, can score partial penetrations on the weapon mount. Given time will mobility kill the tank.

45 degrees: Given time will mobility kill the tank.

90 degrees: can penetrate the upper left hull and kill the tank.

37/21 Puteaux: I would have liked to test it, but I couldn't convince my test Renaults to open fire much - for the most part they just sat there with the commander hanging out of the turret. Firing on them with small arms made them button, but that was it. Every now and then one would stir itself to fire, in which case it would bounce off even the side armour - but I didn't see enough volume of fire to judge whether that was the rule.

37/40 Vickers:

Frontally: No penetrations, no significant damage.

45 degrees: Occasionally scores a partial penetration on the upper side armour. No significant damage.

90 degrees: Can penetrate the upper side armour and kill the tank.

47/32 cannon:

Frontally: Can penetrate the lower front hull and can partially penetrate the upper front hull and weapon mount. Given time will kill or mobility kill the tank.

45 degrees: Can penetrate the upper side hull and partially penetrate the lower side hull, can penetrate the side turret. All my test tanks were mobility killed but not destroyed.

90 degrees: Can penetrate the side turret and kill the tank. None survived sustained fire.

65/17 infantry gun:

Frontally: Can penetrate the front turret and lower front hull with HEAT rounds and kill the tank. There aren't many HEAT rounds so this is rare; the remaining HE is enough to mobility kill the tank given time.

45 degrees: Can partially penetrate the upper side hull. I didn't test as many of these as of the front armour so its possible I missed penetrations by HEAT. In any case, HE is enough to mobility kill the tank given time.

90 degrees: Can penetrate the upper left hull and kill the tank.

75/18 cannon:

Frontally: Can penetrate the lower front hull, upper front hull and weapon mount, can kill, mobility kill or firepower kill the tank.

45 degrees: Can penetrate the upper side hull and side turret and kill the tank. None survived sustained fire.

90 degrees: Can kill the tank. None survived sustained fire.

90/53 cannon:

All aspects: Take a wild guess what happens. ^^

Think I'll do some longer range testing in a bit. I'm keen to find how to stop Shermans reliably with the Italians - the big gunned TDs tend to die in practice 'cause they're too slow to react.

[Mitra76]

Mitra76,

Very much appreciate the detailed explanation! Am thinking BFC could've used you in CMFI the way it did Valera Potapov (www.iremember.ru) for Cmx1's CMBB. I think this EP/EPS/EP 42 issue needs further work, perhaps in the patch.

In one of the links I gave, the spec sheet in Italian for the 65/17, the mitraglia round was mentioned. I presumed, by its similarity to mitrailleuse, that it was canister, since shrapnel was listed elsewhere.

http://en.wikipedia.org/wiki/Mitrailleuse

Regards,

John Kettler

Yes mitraglia corresponds to french mitraille and to english canister.

[Rickusty]

I've lined up some Shermans and had them shot at for a bit with a range of Italian weaponry. Had some tanks at slightly different elevations to ensure they were hit all over.

At very close (200m) range, shooting until ammunition runs out or for up to ten minutes:

20mm ATR:

Frontally: is occasionally able to penetrate the lower front hull, but never does any significant damage.

At 45 degrees sidewards: can score partial penetrations on the upper side hull. Can result in mobility kills if its in a position to hit the wheels.

At 90 degrees side on: can penetrate the upper left hull and kill the tank given time.

20mm Breda autocannon:

Frontally: can occasionally penetrate the lower front hull, can score partial penetrations on the weapon mount. Given time will mobility kill the tank.

45 degrees: Given time will mobility kill the tank.

90 degrees: can penetrate the upper left hull and kill the tank.

37/21 Puteaux: I would have liked to test it, but I couldn't convince my test Renaults to open fire much - for the most part they just sat there with the commander hanging out of the turret. Firing on them with small arms made them button, but that was it. Every now and then one would stir itself to fire, in which case it would bounce off even the side armour - but I didn't see enough volume of fire to judge whether that was the rule.

37/40 Vickers:

Frontally: No penetrations, no significant damage.

45 degrees: Occasionally scores a partial penetration on the upper side armour. No significant damage.

90 degrees: Can penetrate the upper side armour and kill the tank.

47/32 cannon:

Frontally: Can penetrate the lower front hull and can partially penetrate the upper front hull and weapon mount. Given time will kill or mobility kill the tank.

45 degrees: Can penetrate the upper side hull and partially penetrate the lower side hull, can penetrate the side turret. All my test tanks were mobility killed but not destroyed.

90 degrees: Can penetrate the side turret and kill the tank. None survived sustained fire.

65/17 infantry gun:

Frontally: Can penetrate the front turret and lower front hull with HEAT rounds and kill the tank. There aren't many HEAT rounds so this is rare; the remaining HE is enough to mobility kill the tank given time.

45 degrees: Can partially penetrate the upper side hull. I didn't test as many of these as of the front armour so its possible I missed penetrations by HEAT. In any case, HE is enough to mobility kill the tank given time.

90 degrees: Can penetrate the upper left hull and kill the tank.

75/18 cannon:

Frontally: Can penetrate the lower front hull, upper front hull and weapon mount, can kill, mobility kill or firepower kill the tank.

45 degrees: Can penetrate the upper side hull and side turret and kill the tank. None survived sustained fire.

90 degrees: Can kill the tank. None survived sustained fire.

90/53 cannon:

All aspects: Take a wild guess what happens. ^^

Think I'll do some longer range testing in a bit. I'm keen to find how to stop Shermans reliably with the Italians - the big gunned TDs tend to die in practice 'cause they're too slow to react.

Thank you John. Very interesting.

[Erwin]

Useful info. Thanks... (Wish this sort of stuff was in a CM1-like game window at least as an approx guide.)

[John Kettler]

John Johnston,

Appreciate tests. Lower front hull of Sherman houses final drive assembly behind the hull proper. Whole thing unbolts. Sounds like the Solothurn's barely getting through the hull armor but isn't getting through the substantial casing housing the drive. If it did, it's be a sure M-Kill.

John and BFC,

As noted earlier in the ammo split link http://www.comandosupremo.com/forums/topic/5459-effetto-pronto-speciale/ I provided, FULLY 1/3 of the Canone da 65/17's ammo load should be EP, this per the Italians' own documents.

Regards,

John Kettler