but will it be enough? there is also question of whether the much higher muzzle velocity will aid the performance or hamper it- ex. as the impact velocity gets closer to (or starting at 1.6km/s, dunno maybe function of what composition/alloy)2km/s, DU loses its shearing property that handily gives about 10% improved performance against a tungsten counterpart. then there is the minor problem of the gun lacking a fume extractor, you will need an air compressor installed so your crew dont pass out after firing.
me personally i would focus on HEAT rounds for the older tanks- those dont require a very powerful gun and is a very good way to keep the opposing side's armor designers on their toes. they would have to design armor against two very different modes of defeat - heck with the western focus on APFSDS as a sort of gay bulge against armor you could use this to "condition" their designers into making armor that is good enough for APFSDS but horribly inefficient against HEAT.
It would be worthwhile....specially if the auto loader could be modified to fire the new high-penetration long-rods that will be equipped on the T-14. I assuming adding a fume extractor would not be hard.
HEAT is becoming more and more useless by the day... Composites and reactive armor, along with spacing have all put it off of the lime light. There is a reason long-rods are the item to be had right now.
Enough in tank duel at combat relevant ranges? Well no tank has enough penetration nor accuracy to fight that in such environments, they would end up landing mobility, optical and firepower kills before they would land actual kills but that is of low concern since the job is to neutralize the threat from enemies advancing armor it is not your personal duty to kill everyone inside a tank and to make sure every single subsystem is completeley shred to pieces. Destroy the engine and its capability to fight and you already have achieved what you have to achieve, because in this traditional concept of Tank vs Tank you don't have 1 vs1, you have tank formation vs tank formation. You keep on shooting your target untill the gunner sees signs of effect then he moves on to next target, because therea re still enemies that will try to shred you to pieces, so he won't have time to look exactly what kind of damage is done on the tank if he stops shooting back or it looks like he is destroyed through the TIS, you leave him alone and follow next designated target by your commander, but this is of course without everything else on a battlefield like Helicopters, artillery or whatever forces there might be depending on environment.
The gun fume extractor on T-14 is either not installed because the turret is unoccupied or because they haven't finished the actual gun and this is just a mockup, if it is going to be installed on T-90AM then it will get its fume extractor no doubt about that.
I aggree HEAT rounds are unappreciated and underrated by many. Tests of Tandem HEAT rounds have shown that precursor that is designed to destroy ERA has usually 50-100mm RHAe pen. and HEAT rounds with larger precursor can weakening the composite armors interior composition, especially when they reach to ceramics which specifically are good against CE penetrators.
HEAT rounds have some weaknesses:
1. HEAT rounds are largley unoccupied by explosives. The space is needed to form a penetrator.
2. Weight and balance of rounds is ineffecient due the air gaps there needed for penetrators to shape used as a probe.
3. Low speeds and with the problem No. 2 it reduces its accuracy.
Tests and rounds like BK-31M has shown to reduce such problems they also used 3 charges one with an unknown alloy/material for the main HEAT charge. The concept is relative simple and if to be trusted than it is capable to design HEAT rounds that way that a rear HEAT charge can pass through a shaped charge infront of it without detonating it. This arrangement of a rear shaped charge which was not only smaller but also had therefore longer "probe" and time to shape its penetrator means that other materials that are usually disliked to be used in HEAT weapons as a cone liner like Tantal because they need longer probes to form an optimal penetrator can now be used btw which has better properties in armor depth penetration than copper liner against non homogenous armor. HEAT weapons are also usfull against all kinds of targets (Helicopters, Tanks, IFV/APC's, Infantry (even tho less effective than HE-Frag)) while Sabots are only usefull Frontal engagement against Tanks, highly uneffective to useless against Helicopters, AFV/IFV/APC, Infantry etc.
HEAT rounds have not met their limit yet, not to mention that the West reject using ERA on their armor which makes HEAT rounds more useful with precursor opening armor and weakning some depth of armor makes it more capable for main charges to perforate more armor and with more development for more charges with different liner materials and alloys will show great potential for rounds. The heavier such rounds get the higher the velocity of such rounds can be made without losing to much of accuracy.