Such issue was first pointed out two days ago when I posted the datamined results of Gaijin’s slope effect modifiers on a Chinese WT forum. Commenters below my post quickly noticed that the APDS shots have a sketchy penalty curve. To understand such issue, we must first have a look inside Gaijin Entertainment LLC’s black magic of how their slope modifiers work: Here are some extracted codes from damagemodel.blk:

"slopeEffect0deg": [0.0,20.0],
"slopeEffect5deg": [5.0,17.0],
"slopeEffect10deg": [10.0,15.0],
"slopeEffect15deg": [15.0,10.24],
"slopeEffect20deg": [20.0,7.2],
"slopeEffect25deg": [25.0,3.72],
"slopeEffect29deg": [29.0,2.76],
"slopeEffect30deg": [30.0,2.46],
"slopeEffect35deg": [35.0,2.24],
"slopeEffect40deg": [40.0,2.064],
"slopeEffect45deg": [45.0,1.8],
"slopeEffect50deg": [50.0,1.4],
"slopeEffect55deg": [55.0,1.2],
"slopeEffect60deg": [60.0,1.024],
"slopeEffect65deg": [65.0,1.0],
"slopeEffect70deg": [70.0,1.0],
"slopeEffect75deg": [75.0,1.0],
"slopeEffect80deg": [80.0,1.0],
"slopeEffect85deg": [85.0,1.0],
"slopeEffect90deg": [90.0,1.0]

The [X, Y] values in the brackets are where magic happens: X value determines the angle of the armor (0 degrees meant that the shell is parallel to the armor plate, while 90 degrees indicate a perfectly flat plate. This value basically means how many degrees off from parallel is the shell with the plate.), while the Y value determines the penetration penalty to such slope. For example, an APDS shot undergoes a penetration decay of 2.46 times when it hits a plate that’s angled 60 degrees, or 30 degrees away from the parallel position. Pretty logical, huh? Let’s see it in action.