The PT-76 is considered on of the worst tanks in era 1, and to fix that it would need several changes. Since the tank cannot mount a gun rammer, I would suggest changing the 57mm to a proper auto-cannon, and give the tank some weight reductions, and a 76mm alpha buff. My idea behind the auto-cannon stats is to keep its DPM and RPM the same, thats why I gave it a 28.5s reload. With a clip size of 20, itd have a clip potential of 2100, (which is historical, but may be a bit high). I do feel as the 20 round clip may be somewhat balanced by the overall slower speed, tall vehicle height, and 9.5s unload time. The weight reduction is to make slightly more mobile without making any drastically different ahistorical changes.
If the clip potential is too high, the weight changes may not be needed. It would keep its rather sluggish mobility that way.
-- General Changes (Completely Stock)
-- Vehicle Weight: 14.48 -> 14
-- 76mm
-- Alpha: 150 -> 180
-- Reload: 3.2s -> 3.8s
-- DPM: 2812 -> 2842
-- Engine 1 (Gun and Turret 1)
-- Power to Weight: 16.57 -> 17.1
-- 57mm
-- Gun Depression: -4 -> -5
-- Penetration: 160/205/53 -> 151/42
-- Fire Type: Single Shot -> Auto-Loader
-- Clip Size: 1 -> 20
-- Reload: 1.9s -> 28.5s
-- Intra-Clip: 0.5s
-- DPM: 3316 -> 3315
-- RPM: 31.58 -> 31.57
-- Engine 2 (Gun 1 and Turret 1)
-- Power to Weight: 20.95 -> 21.42
-- Engine 2 (Gun and Turret 2)
-- Vehicle Weight: 15.87 -> 15
-- Power to Weight: 18.9 -> 20