anyway, we were talking about the existence of ukrainian guns in general...
This is off the official (90%sure) Karkiv Morozov site. Is this useful?
125 mm KBA3 tank gun is installed in main battle tanks Oplot and T-80UD.
It is successfully used when modernizing armoured vehicles, for example, tanks T-62.
It serves to:
to defeat tanks and other armoured vehicles of the enemy;
to suppress and destroy fire support means and personnel of the enemy.
KBA3 gun can fire separate-loading ammunition, including:
guided missiles (GM)
armour-piercing discarding sabot fin-stabilized projectile (APDSFS)
high-explosive antitank projectile (HEAT)
high explosive-fragmentation projectile (HE-FRAG)
air-bust fragmentation-shrapnel projectile (ABFS)
Specifications of the gun
Designation KBA3
Calibre 125 mm
Type smoothbore gun
Breech-block type semiautomatic with horizontal placement of the wedge
Gun length 6678 mm
Barrel length 6000 mm (L48)
Normal recoil length 260 to 300 mm
Maximum possible recoil length (STOP) 310 mm
Initial pressure in the recuperator 59 to 62 kgf/cm2
Number of recoil brakes 2
Placement of recoil brakes symmetrical relative to the gun bore axis
Number of recuperators 1
Resistance to recoil 98000 kgf
Gun weight 2500 kg
Weight of gun recoiling part 1900 kg
Muzzle velocity (when firing 3VBM17 "MANGO" armour-piercing round) 1700 m/s
Maximum acceptable calculated gas pressure in charge chamber 6500 kgf/cm2
Gas pressure in charge chamber (when firing 3VBM17 "MANGO") 5660 kgf/cm2 (at t=15°C)
Horizontal dispersion (APDSFS and HEAT at 2000m range) 0.2 mils
Vertical dispersion (APDSFS and HEAT at 2000 m range) 0.2 mils
