Posted 22 August 2003 by Eduardo
I've read that Italian 47mm were also provided with EP rounds. It surprises me. It's that true. When they started to be used by Italian units in the field.
Does anybody know its performance and availability?
Thank you.
Eduard
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Posted 23 August 2003 by SM79Sparviero
Effetto Pronto 47 mm shells were available but the gunners soon realized they were much worse than usual 47 mm kinetic armour piercing shells.
EP is an hollow-charge shell, or HEAT. The power of the high-temperature high speed metallic jet that pierces the armour is directly related to the diameter of the shell, a 75 mm shell from a 75/18 howitzer could easily destroy a Sherman or a Grant but a 47 mm shell is too small!
Moreover, a HEAT shell generates an effective concentrated metal dart if its terminal speed is not too high, as in a short howitzer ( 350-400 m/sec.) .The 47 /32 mm Ansaldo Italian gun was projected to shoot hard armour-piercing shells at high speed to hit a moving target as a tank ( 700 m/s and more).
I think that an EP shell would have been more useful for anti-tank fighting at low range with the small Brixia 45 mm mortar just for the low speed of its grenades.
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Posted 25 August 2003 by Eduardo
Thanks for the information.
Even though 47mm is just a little lower diameter than a bazooka. The effect vs armour should not be so different?
Ed
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Posted 25 August 2003 by SM79Sparviero
The first Bazooka launched 57 mm ( 2.75 inches) shells.It could not seem very far from a 47 mm Effetto Pronto , but the piercing power of an hollow charge jet is related to the diameter of the shell by a QUADRATIC ratio, not a linear one.That's a jet generated by a 4 cm shell is more powerful than the similar from a 3 cm shell as 16 related to 9 and not as 4 related to 3!
Moreover, a HEAT shell can create a good armour-piercing jet if the shell is not too fast and if it doesn' t revolve around its axis.It has always been a good anti-tank weapon if used at short range.
In the more powerful 88 mm bazooka the projectile's flight path was stabilized by a sheet metal stabilizer ring at the rear of its shaft looking quite similar to those used on aircraft bombs. The propellant continued to burn even after it left the tube for another 2m , the projectile had then reached its velocity of 105m/s.
The Italian 47 mm Effetto Pronto shell was stabilized by the spin around its main axis imposed by the barrel of the gun, this spin and the terminal high speed ( 700 m/sec.)of the shell increased the probability to hit a target at long range but in the same time they made an interference with the jet of the hollow charge.
According to me a 45 mm HEAT shell for the Brixia mortar would have been more useful at short range for the low speed of the shell and for the absence of a spin.
I've read that Italian 47mm were also provided with EP rounds. It surprises me. It's that true. When they started to be used by Italian units in the field.
Does anybody know its performance and availability?
Thank you.
Eduard
------------------
Posted 23 August 2003 by SM79Sparviero
Effetto Pronto 47 mm shells were available but the gunners soon realized they were much worse than usual 47 mm kinetic armour piercing shells.
EP is an hollow-charge shell, or HEAT. The power of the high-temperature high speed metallic jet that pierces the armour is directly related to the diameter of the shell, a 75 mm shell from a 75/18 howitzer could easily destroy a Sherman or a Grant but a 47 mm shell is too small!
Moreover, a HEAT shell generates an effective concentrated metal dart if its terminal speed is not too high, as in a short howitzer ( 350-400 m/sec.) .The 47 /32 mm Ansaldo Italian gun was projected to shoot hard armour-piercing shells at high speed to hit a moving target as a tank ( 700 m/s and more).
I think that an EP shell would have been more useful for anti-tank fighting at low range with the small Brixia 45 mm mortar just for the low speed of its grenades.
--------------------
Posted 25 August 2003 by Eduardo
Thanks for the information.
Even though 47mm is just a little lower diameter than a bazooka. The effect vs armour should not be so different?
Ed
--------------------
Posted 25 August 2003 by SM79Sparviero
The first Bazooka launched 57 mm ( 2.75 inches) shells.It could not seem very far from a 47 mm Effetto Pronto , but the piercing power of an hollow charge jet is related to the diameter of the shell by a QUADRATIC ratio, not a linear one.That's a jet generated by a 4 cm shell is more powerful than the similar from a 3 cm shell as 16 related to 9 and not as 4 related to 3!
Moreover, a HEAT shell can create a good armour-piercing jet if the shell is not too fast and if it doesn' t revolve around its axis.It has always been a good anti-tank weapon if used at short range.
In the more powerful 88 mm bazooka the projectile's flight path was stabilized by a sheet metal stabilizer ring at the rear of its shaft looking quite similar to those used on aircraft bombs. The propellant continued to burn even after it left the tube for another 2m , the projectile had then reached its velocity of 105m/s.
The Italian 47 mm Effetto Pronto shell was stabilized by the spin around its main axis imposed by the barrel of the gun, this spin and the terminal high speed ( 700 m/sec.)of the shell increased the probability to hit a target at long range but in the same time they made an interference with the jet of the hollow charge.
According to me a 45 mm HEAT shell for the Brixia mortar would have been more useful at short range for the low speed of the shell and for the absence of a spin.
Unfortunately there is still alot of head scratching as to what is correct. I found USA manuals of enemy shells and German tests of some of these guns, also WWII Ballistics: Armor and Gunnery, by Bird and Livingston has "international" standardised Italian AT cannon . Also