12cm HEAT shell
the 12cm AKAN historically was one of three planned armaments for the EMIL prototype, which never saw actual production. I cant find sources for how these rounds would have performed, but in addition to APDS the gun could also fire fin stabalized HEAT shells and a unique experimental ammo type that was a hybrid of APDS and HEAT. so basically tandem HEAT but one of the charges is an APDS round instead.
Itd be nice if the AKAN got a HEAT shell with around 250-300mm of pen, with the downside being lackluster damage. a special tandem HEAT shell with less pen but anti-ERA and anti-composite capability would also be nice. Id say this one has around 250mm of pen, for balance. Maybe have two different penetration values, or have a negative modifier to penetration against ERA/Composites. Point is itd be a fun round to have in game.
https://en.wikipedia.org/wiki/Emil_(tank)
IRL the round wouldve been 350-400 pen, but obviously thatd be busted for T8 especially with 5s reload.