How does shell penetration vs armor works in game?

[Companion]

I know SB uses abstracted RHAe estimation for both shell and armor but Is there some sort of close range bonus? Values slightly randomized maybe?

I played a Zipuli's scen just now with friends but with equipment edited

I thought M829A2 (770mm pen) would be not so reliable against T-90A glacis (800mm) even after accounting for vertical angle changes due to terrain but well, the round (thankfully) never failed once (cheked the AAR).

Map being Finnish restricted terrain, virtually all fight occured under 2km, mostly about battlesight ranges. Maybe the range mattered?

Any info would be helpful for those of us who likes to swap equipment in otherwise well balanced scenario; frankly, M1A2 w/ M829A2 vs T-90A w/BM42M felt rather easier than using M1A1HA against BM42 armed T-72M1.

I know I should've playtested beforehand but equipment changes like that usually happens impulsively at the last moment :1:

[Invader ZIM]

I'm certainly no expert on this, but could it be the rated penetration value of the M829A2 is the penetration at a certain range?

I've seen some figures quoted on the various tank rounds in the SBWiki, and they seem to be ratings out to around 2km. So if the 770mm value is for penetration at 2km, and you mentioned you were under that range when engaging, you were possibly giving the M829A2 enough headroom to penetrate the T-90's heavier protected areas. I'm certain that closing the range against your targets does increase the penetrative power of the Kinetic Energy rounds as they have more velocity.

Have you tried your scenario with M829A1's instead at those ranges?

[Companion]

I'm certainly no expert on this, but could it be the rated penetration value of the M829A2 is the penetration at a certain range?

I've seen some figures quoted on the various tank rounds in the SBWiki, and they seem to be ratings out to around 2km. So if the 770mm value is for penetration at 2km, and you mentioned you were under that range when engaging, you were possibly giving the M829A2 enough headroom to penetrate the T-90's heavier protected areas. I'm certain that closing the range against your targets does increase the penetrative power of the Kinetic Energy rounds as they have more velocity.

Have you tried your scenario with M829A1's instead at those ranges?

Didn't P0 meant pen at muzzle? Editor has pen values at "P0"

I'll be sure to use A1 next time around

Or I can just use chally :clin:

[dejawolf]

I know SB uses abstracted RHAe estimation for both shell and armor but Is there some sort of close range bonus? Values slightly randomized maybe?

I played a Zipuli's scen just now with friends but with equipment edited

I thought M829A2 (770mm pen) would be not so reliable against T-90A glacis (800mm) even after accounting for vertical angle changes due to terrain but well, the round (thankfully) never failed once (cheked the AAR).

Map being Finnish restricted terrain, virtually all fight occured under 2km, mostly about battlesight ranges. Maybe the range mattered?

Any info would be helpful for those of us who likes to swap equipment in otherwise well balanced scenario; frankly, M1A2 w/ M829A2 vs T-90A w/BM42M felt rather easier than using M1A1HA against BM42 armed T-72M1.

I know I should've playtested beforehand but equipment changes like that usually happens impulsively at the last moment :1:

if you're hitting centerpoint in the area around the drivers vision block you could be hitting the weakened glacis area. there's a fairly large cutout for the driver where the protection is only about ~621mm vs KE. it extends to the width of the coax port, and stretches downward somewhat below the mudshield on the glacis.

[Companion]

if you're hitting centerpoint in the area around the drivers vision block you could be hitting the weakened glacis area. there's a fairly large cutout for the driver where the protection is only about ~621mm vs KE. it extends to the width of the coax port, and stretches downward somewhat below the mudshield on the glacis.

I did some shootout test, about 2km, only did about few dozen targets though

Using the armor paint picture you've posted earlier as reference:

http://www.steelbeasts.com/sbwiki/images/9/9f/T90armour.jpg

except for the 4-digit protection level corners, the whole glacis is a fair game for M829A2. Target tank either dies or gets damaged after every hit on that location.

[MAJ_Fubar]

I've been running a few (admittedly unscientific) tests with various ammo types against the the T-90 and have noticed that most rounds later than the M829/DM33 generation are more than capable of taking the beast under 2500m. This may have a lot to do with a given tanks inherent accuracy (i.e. thanks to the CR2s good accuracy, even the crappy L27 performs well at those ranges), or perhaps it's that round to round dispersion doesn't really come in to effect below 3000m (e.g. the Slpprj m/95 appears to be a particularly poor performer because it seems to be everywhere on the target). Of course, its got a weak chin, and just about any hit below the front hull glacis is a guaranteed kill.

[Invader ZIM]

You guys are right, didn't realize P0 was at the muzzle penetration. Will have to consider that for some of my scenario and ammo edits, heh.

[Volcano]

I thought M829A2 (770mm pen) would be not so reliable against T-90A glacis (800mm) even after accounting for vertical angle changes due to terrain but well, the round (thankfully) never failed once (cheked the AAR).

Edited:

Ignore my post. I was talking about post penetration effect and you were asking about the round penetrating in the first place. :eek:

[Companion]

I've been running a few (admittedly unscientific) tests with various ammo types against the the T-90 and have noticed that most rounds later than the M829/DM33 generation are more than capable of taking the beast under 2500m. This may have a lot to do with a given tanks inherent accuracy (i.e. thanks to the CR2s good accuracy, even the crappy L27 performs well at those ranges), or perhaps it's that round to round dispersion doesn't really come in to effect below 3000m (e.g. the Slpprj m/95 appears to be a particularly poor performer because it seems to be everywhere on the target). Of course, its got a weak chin, and just about any hit below the front hull glacis is a guaranteed kill.

You are talking about chance of hitting the weakly protected area on or near the tank's center mass.

I was talking specifically about chance of penetrating the target when the shell hit the protected area of frontal hull glacis, not weak areas.

[dejawolf]

attached a pic outlining the weakened area of the hull.

[Companion]

attached a pic outlining the weakened area of the hull.

Thanks for the picture

So I've shot a few dozen more T-90s (shootings at about 1km) and results don't quite match with the picture.

Added some screenshots. It seems M829A2 has a very high chance of getting through T-90A glacis.

M829A1 seems to be able to pen only the driver cutout you've mentioned and the bottom of Kontakt block at the lower part of glacis.

I also blew up a few T-80Us with M829A1 and it seems as if penetration is somewhat random within a boundary.

In the T-80U screenshot, M829A1 sometimes pen and sometimes doesn't on that very spot on the glacis.

Maybe AAR is not perfect as to showing exact hit location or I am doing something wrong?

Oh, and one more thing: Does SB take into account the edges of each Kontakt block? The shooting I just did and past memory seems to suggest that M829A1 had a high chance of killing T-80U when landed on the seams where Kontakt blocks join together.

[dejawolf]

Thanks for the picture

So I've shot a few dozen more T-90s (shootings at about 1km) and results don't quite match with the picture.

Added some screenshots. It seems M829A2 has a very high chance of getting through T-90A glacis.

M829A1 seems to be able to pen only the driver cutout you've mentioned and the bottom of Kontakt block at the lower part of glacis.

I also blew up a few T-80Us with M829A1 and it seems as if penetration is somewhat random within a boundary.

In the T-80U screenshot, M829A1 sometimes pen and sometimes doesn't on that very spot on the glacis.

Maybe AAR is not perfect as to showing exact hit location or I am doing something wrong?

Oh, and one more thing: Does SB take into account the edges of each Kontakt block? The shooting I just did and past memory seems to suggest that M829A1 had a high chance of killing T-80U when landed on the seams where Kontakt blocks join together.

yes Sb takes into consideration the edges of the ERA blocks. on the sides of the front hull where the headlights are for example, there's no ERA blocks. but some of those kills looks strange though.. most of those locations are at least 800mm LOS in the armour model.

[Companion]

yes Sb takes into consideration the edges of the ERA blocks. on the sides of the front hull where the headlights are for example, there's no ERA blocks. but some of those kills looks strange though.. most of those locations are at least 800mm LOS in the armour model.

If the results seem strange even to you, there might indeed be a problem...

I hope it's not too complicated.

On a side note, I'm getting a mixed results from shooting T-64A/B with old 105mm rounds. It's as if A is better armored than B...

At least both models' glacis KE resistance seems to be around 330. correct?

[Volcano]

At least both models' glacis KE resistance seems to be around 330. correct?

Yes, identical in all respects -- every single value (verified). So, if you perceive a difference then it is down to the subtle difference in round placement and luck.

[Companion]

Yes, identical in all respects -- every single value (verified). So, if you perceive a difference then it is down to the subtle difference in round placement and luck.

So both models have identical armor? Thank you for information.

That explains a lot... though I did nowhere near enough repetitions to make even a remotely valid statistic lol :c:

I took it for granted that in game A and B models would differ in armor model, B being later mod and all. But couldn't be so sure with what Esimgames chose among all those myriad of Soviet changes to T-64 armor configurations.