Penetration of guns against armour

[mav1]

This is a confusing issue, both cmbb and cmak had different penetration values. So can a penetation value be agreed on. There is a lot of conflicting statistics out there. But will it be even harder to agree on the penetration values for cmsf, as some of this info is classified.

Does anyone know what the penetration values of guns will be in cmsf.

[MikeyD]

Peneration values changed from CMBB to CMAK because of advances in research on the topic. I'm trying to recall who it was who lead the charge for accurate penetration data. Perhaps it was Lorrin Bird who authored the book "World War II Ballistics: Armor & Gunnery".

Penetration values in CMSF? Nobody who knows is telling! Between DU penetrators, explosive-formed projectiles, tandem warheads, and composite/reactive armor I can't imagine penetration values in CMSF being much better than 'best estimate'. I once came across a number for the armor steel equivalent of the M1A2 Abram's composite turret front. it was some obscenely high number. Again my fading memory is failing me - does equivalent 14 feet of steel sound right?

[ June 05, 2006, 01:03 PM: Message edited by: MikeyD ]

[ParaBellum]

Originally posted by MikeyD:

Again my fading memory is failing me - does equivalent 14 feet of steel sound right?

No, that doesn't sound right. The estimates I have seen so far range from ~1000-1600mm equivalent of steel for the front armour for the M1A2, depending on the type of round (HEAT or APFSDS).

[MikeyD]

Yikes I was off! 1600mm = about 5 1/4 feet of steel - still nothing to sneeze at.

Now that i think of it 1600mm was about what I heard too, i'm just lousy at metric conversion

[flamingknives]

Just remember that 1600mm is liable to be maximum effective thickness and is liable to be much less elsewhere.

[mav1]

I think the german gun penetration values were more accurate in cmbb apart from the 75/48, 88/71 and 75/24, which were more accurate in cmak. Unless new info has come about that I don't know about.

By the way how much can a abrams firing an apfds round can penetrate? Is there anyone in the forum, who has worked with abrams tank's and knows the secret.

[flamingknives]

Best guesses are in the region of 800 - 900mm RHAe.

I don't imagine that you'll find anyone who knows for definate telling you though...

Plus, 1600mm is peak effectiveness against shaped charges, which are alot easier to defeat than long-rod penetrators.

As for accuracy of figures in CM, What are you comparing them too? Remember as well that the figures in the unit data screen are vs. a typical enemy, not absolute figures. AIUI Russian armour plate was somewhat different in makeup and properties than Western allies plate.

[MikeyD]

Yeh, I recall BFC's main benefit has been helping to do a fair amount of myth-busting in the genre. Just because the game doesn't match your assumptions (or someone elses stats) doesn't mean its wrong.

I've been searching for 120mm gun penetration stats without much luck. I suppose most-any armor fielded by Syria at most-any range compatible with a CM map (assuming something equivalent to CMx1), the APFSDS will penetrate. The fun part will come playing blue-on-blue games. At what range will an Abrams KO an Abrams?!

[flamingknives]

http://members.tripod.com/collinsj/protect.htm

It all seems fairly sensible.

[Andrew H.]

Originally posted by mav1:

I think the german gun penetration values were more accurate in cmbb apart from the 75/48, 88/71 and 75/24, which were more accurate in cmak. Unless new info has come about that I don't know about.

I'm not sure that the penetration values actually changed at all. When CMAK first came out, there was some discussion of apparently different penetration values as reflected in the stats in the information screen. Apparently, though, the actual penetration values hadn't changed, only the numbers given in the stats box. And these numbers were changed because, IIRC, the type of armor used on US tanks had a different hardness than the type used on soviet tanks, and the number in the info box reflected the penetration vs. the most common armor that would be faced.

BUT - the actual penetration value hadn't changed, and the actual penetration in the game would depend on what armor the projectile was actually trying to penetrate.

This is kind of vague and half remembered, but you could probably find more details by doing a search. Also, some penetration calculations were refigured, I think. But for the majority of seemingly changed penetration values, there was in fact no calculation change between the games.

[MikeyD]

From Flamingknives's great link:

US M829A3 120mm DU 765mm at 2km (200x) (Russian estimate 795mm

---

Versus

Export T72 armor equivalents vs KE rounds:

Turret: 280-380 

Upper front turret: 180

Glacis: 335

Lower front hull: 200

and here's the T72B;

Turret: 280-540     

Glacis: 485

Lower front hull: 250

Translation - 120mm APFSDS penetrations at 2km pretty much guaranteed. And most CMx1 maps rarely have LOS out to 2km due to the terrain.

But things get interesting comparing the Stryker's 105mm gun. Mecar (I believe) is producing the new 105mm APFSDS. Im not sure what this rounds properties may be:

Mecar 105mm tungsten APFSDS 390mm at 2km

US M-833 105mm DU 440mm at 2km

That makes it a near thing versus a T72B at 2km (and explains why the U.S. dropped the 105mm gun!).

[mav1]

The russian tank armour is thin compared to the abrams. So how thick is the t80 and t90's armour?

Is the challenger 2 tank armour thicker than an abrams tank?

How much can the centurion 105mm can penetrate? The British were worried about the is-3 so can the 105mm penetrate the frontal armour of a 1s-3.

[ June 20, 2006, 05:10 AM: Message edited by: mav1 ]

[flamingknives]

105mm L7 ought to do for an IS3. The Centurion was initially armed with a 17pr (76.2mm), then a 20pr (84mm) gun. Both were insufficient to deal with the IS3, hence the introduction of the Conqueror heavy gun tank. However, the introduction of the 105mm gun rather put paid to the heavy gun tank concept, so it must have been up to the task. The 105mm armed Israeli tanks did have trouble with Arab T55s, but not whatever other heavies that might have been around.

The link above has the most comprehensive and seemingly correct information I've seen on the 'net.