Armor penetration of HE shells
Posted: Wed Jan 08, 2014 12:14 pm
Gentlemen,
please forgive me to open here a can full of worms but I wonder about the armor penetration of HE shells.
I have read at http://www.navweaps.com/index_nathan/Pe ... _index.htm :
"According to Nathan Okun, a nose-fuzed projectile would penetrate 0.2 calibers of homogeneous ductile plate (obliquity not important when filler explodes in most cases) or 0.3 calibers of a face-hardened KC-type plate. Thus a typical 5” gun firing a nose-fuzed projectile would penetrate 1.0” of homogeneous armor or 1.5” of face-hardened armor throughout its range, with most of the penetration from the explosive force of the burster rather than kinetic energy."
While I have great respect for Mr Okun's expertise, I am a bit surprised for two reasons.
First, the difference in deck armor penetration appears very low between AP and HE shells.
According to http://www.navweaps.com/Weapons/WNUS_16-50_mk7.htm a USN 16"/50 AP shell penetrates 3.9" of deck armor at 20.000 yards, which is rather close to the 3.2" (16" x 0.2) that the HE shell is supposed to penetrate.
The numbers are even stranger for 8" guns (http://www.navweaps.com/Weapons/WNUS_8-55_mk9.htm). The HE shells penetrate 1.6" of deck armor while the AP one defeats 1.5" at 17.600 yards and 2" at 21.200 yards. Hence at battle range HE shells perform as well as (or better than) AP ones. I may be mistaken but that sounds strange for me.
Then, another article by Mr Okun (http://www.navweaps.com/index_nathan/Mi ... scarmr.htm) shows a formula which gives different results. For most circumstances, HE shells are said to penetrate 0.156 of STS plate (plus a small bonus for the projectiles which keep a high velocity).
Thank you for any help,
Francis Marliere
please forgive me to open here a can full of worms but I wonder about the armor penetration of HE shells.
I have read at http://www.navweaps.com/index_nathan/Pe ... _index.htm :
"According to Nathan Okun, a nose-fuzed projectile would penetrate 0.2 calibers of homogeneous ductile plate (obliquity not important when filler explodes in most cases) or 0.3 calibers of a face-hardened KC-type plate. Thus a typical 5” gun firing a nose-fuzed projectile would penetrate 1.0” of homogeneous armor or 1.5” of face-hardened armor throughout its range, with most of the penetration from the explosive force of the burster rather than kinetic energy."
While I have great respect for Mr Okun's expertise, I am a bit surprised for two reasons.
First, the difference in deck armor penetration appears very low between AP and HE shells.
According to http://www.navweaps.com/Weapons/WNUS_16-50_mk7.htm a USN 16"/50 AP shell penetrates 3.9" of deck armor at 20.000 yards, which is rather close to the 3.2" (16" x 0.2) that the HE shell is supposed to penetrate.
The numbers are even stranger for 8" guns (http://www.navweaps.com/Weapons/WNUS_8-55_mk9.htm). The HE shells penetrate 1.6" of deck armor while the AP one defeats 1.5" at 17.600 yards and 2" at 21.200 yards. Hence at battle range HE shells perform as well as (or better than) AP ones. I may be mistaken but that sounds strange for me.
Then, another article by Mr Okun (http://www.navweaps.com/index_nathan/Mi ... scarmr.htm) shows a formula which gives different results. For most circumstances, HE shells are said to penetrate 0.156 of STS plate (plus a small bonus for the projectiles which keep a high velocity).
Thank you for any help,
Francis Marliere