How effective was the 90mm M3 gun?

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Second try
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How effective was the 90mm M3 gun?

Post by Second try » 05 Dec 2002 21:07

Hi everyone!:)

90mm M3 L/50 late M82 APCBC HE 2800 feet/second against RHA angle 30...used also T33 (re-tempered M77,HE, a few M304 HVAP)

129mm at 500m...122mm at 1000m...114mm at 1500m...106mm at 2000m.

M304 HVAP (tungsten cored high velocity armor piercing) 3350 feet/sec
221mm at 500m...195mm at 1000m...177mm at 1500m...154mm at 2000m

These are probably VERTICAL impact values (it wasn't signed)M82...183mm at 100m...170mm at 500m...155mm at 1000m...129mm at 2000m...M304...305mm at 100m...275mm at 500m...242mm at 1000m...187mm at 2000m.

How effective could be the M36 Jackson/M26 Pershing against various type of german armored fighting vehicles? 8),as I know ,there wasn't significant difference between US made and german armor steel. At which combat ranges were effective from the front against...

Panther G: 80mm rolled front upper hull sloped 55-equals 136mm sloped 30...110mm cast round gun shield (88mm in RHA), rolled front turret 110mm sloped 20 equals 94mm sloped 30.

Front hull vertical:170mm
Mantle:88mm round by 30 degree impact 110mm

Jagdpanther:80mm rolled superstructure sloped 55-equals 136mm sloped 30...100mm cast (80mm RHA)Saukopf gun shield.

Superstructure vertical:170mm

Hetzer:60mm rolled superstructure sloped 60-equals 120mm sloped 30...60mm cast (48mm RHA) Saukopf gun shield.

Supersructure vertical:150mm

Jpz IV 70 V:rolled hull 80mm sloped 45-equals 108mm sloped 30...80mm superstructure sloped 50-equals 120mm sloped 30...80mm (64mmRHA)cast Saukopf gun shield.

Hull vertical:135mm
Superstructure vertical:150mm

Tiger II:rolled superstructure 150mm sloped 50 equals 225mm sloped 30...rolled front turret 180mm sloped 10 equals 145mm sloped 30...100mm cast(80mm RHA)Saukopf gun shield.

Hull vertical:285mm
Turret vertical:181mm

PzIVH: rolled front hull 80mm sloped 10 equals 64mm sloped 30...50mm cast gun shield sloped 10-30 equals 40mm RHA...50mm front turret sloped 10 equals 40mm sloped 30.

Hull vertical:80mm
Mantle round:50mm by 30 degree impact

Tiger I:rolled front hull 100mm sloped 10 equals 81mm sloped 30...cast gun mantle 120mm (90mmRHA)sloped 10 equals 77mm sloped 30.

Hull vertical:100mm
Mantle vertical:96mm

I think,armor values are clearly seen but how change the effective armor thicknesses when impacting a 90mm gun projectile ( I mean thickness/diameter of projectile)? :?Because I don't know how these comes out.

So one question would be what's the Hetzer's effective armor thickness against a 90mm projectile?

I attach this to clear changing armor thickness:

Slope (degrees) Multiplier Divisor
10 1.01 0.99
15 1.03 0.97
20 1.07 0.935
25 1.15 0.87
30 1.25 0.8
35 1.37 0.73
40 1.52 0.658
45 1.69 0.59
50 1.89 0.53
55 2.13 0.47
60 2.5 0.4

As I see without knowing different effective armor thicknesses,90mm M3 gun using normal late M82 APCBC HE easily penetrates PzIVH and PzVIE's front armor over 2000m,penetrates Panther G's turret at 2000m by 30 degree impact,Hetzer's superstructure at about 500m,JpzIV 70V's hull at 1000m,superstructure at 500m,Jagdpanther's superstructure except gun shield is immune against normal 90mm projectile as Panther G's front hull. Tiger II is immune from the front as well.But tungsten cored HVAP ammunition pens Jagdpanther at 2000m,Tiger II's front turret over at 1500m when being hit.

90mm "APDS" (I think that is actually HVAP) Probability of a first round hit (not kill) of a tank gun firing at a tank-sized, standing target. Important,percent values are for first hit,not average (which values are more accurate).A skilled and experienced gunner could reach better and worse of course.

90 percent at 500m...65 percent at 1000m... 31 percent at 1500m...14 percent at 2000m.

M26 Pershing had 114mm cast round gun mantle 92mm RHA defense by 30 degree impact. Cast upper hull was 102mm (82mm RHA)sloped 46 equals 140mm vertical and 112mm sloped 30 RHA armor.

It looks Tiger I could pen the hull only at POINT BLANK range using the most common PzGr39 APCBC HE projectile,turret could pen under 1000m by 30 degree impact.75mm Pak39/Kwk40 could pen the turret at under 500m or POINT BLANK by 30 degree impact,hull is immune.Panther's 75mm L/70 gun could pen the turret under 1500m,the hull at 600m. Jagdpanther could pen the turret and the hull over 2000m.

I repeat,different effective armor thickness (T/D) is not calculated,I don't know how it works. :cry:

How am I correct? :wink:

Respectfully...Col.Valentine :)

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