Uh, I never realized that a shell fired by a tank was several times supersonic
By the way they penetrated eachother, one of the projectile seems much softer than the other.
It depends on the type of gun. Short barrelled guns fire subsonic or barely supersonic explosive shells designed purely for anti-personnel/building. Usually fat, large calibre jobs as well like the stubby gun on the Panzer 4 or big mortar jobs on the Brumbar.
Long barrel guns (like the 88) tend to be anti armour, firing high density solid shells at really high velocity for that good kinetic punch. Also, high velocity means 'flat' trajectory and with moving targets that makes hitting things at 2km
much easier.
Fun Fact:
Long barreled versions of shorter gunned tanks (think the 76mm Sherman/Firefly, long gun 75mmm Panzer IV etc) used to be considered higher priority as targets in tank ambushes because of the more capable gun. So crews used to camouflage the extra barrel length and even make fake muzzle brakes 3/4s of the way down the barrel so they'd look like the less lethal versions at distances in the hope they wouldn't get nailed first.
It's one of the things that pissed me off about Fury. The lead tank is a Firefly, and the only one capable hurting a Tiger. The Germans would have known that and would have picked that one for initiating the ambush. Then he'd have nailed the rear one, trapped the convoy and proceeded to mop up the rest of the Shermans at leisure. This was
standard doctrine for heavy armour battalions in the Wermarcht.
But, plot armour is KwK 88 proof, even at 500metres.
There's a trade off there between calibre and velocity though, high calibre tends to be lower velocity and allows a bigger shell for more explosives but a larger surface area when it came to transferring energy against armour which lowered penetration. The 88 sat in the middle ground as a sweet spot between being really good anti infantry artillery, a decent heavy anti aircraft gun and the best anti armour weapon of WWII (Its been described before, with the exception of the atomic bomb, as the most potent killing tool of WWII).
When anti armour moved away from kinetic to HEAT rounds post war, it allowed big calibre guns to do both anti-personnel and anti armour.
Until the invention of APFSDS (Armour Piercing, Fin Stabilised, Discarding Sabot) ammunition that is. That allows a very small, very dense dart made of tungsten to be fired at ridiculous velocities from a very big long gun (the dart from the
120mm on Challenger II leaves the muzzle at 1500m/s) surrounded by a petalled sabot casing to create a seal on the large barrel that splits off when it leaves the muzzle.
The same gun fires a large HESH all purpose round at only 670m/s for buildings, people, fortifications and works well on light/medium armour as well.
Which allows it to not only be capable of killing absolutely anything it can see but also firing a dart into almost LEO in SFS.