Well let's compare the guns in question:
8.8cm KwK43 Pak43 L/71
Projectile weight: 10.4 kg PzGr.39/43 APCBC(HE)
Sectional Density: 1.342
Muzzle Velocity: 1000 m/s
Total Kinetic Energy: 5200 KJ
Kinetic Energy pr. cm^2: 85.49 KJ
Performance against 90 degree 240 BHN RHA armour:
500m = 219mm
1,000m = 204mm
1,500m = 190mm
2,000m = 176mm
2,500m = 164mm
3,000m = 153mm
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7.62cm 17pdr
Projectile weight: 7.7 kg Mk.8T APCBC
Sectional Density: 1.326
Muzzle Velocity: 883 m/s
Total Kinetic Energy: 3001 KJ
Kinetic Energy pr. cm^2: 65.8 KJ
Performance against 90 degree 240 BHN RHA armour:
500m = 163mm
1,000m = 150mm
1,500m = 137mm
2,000m = 126mm
2,500m = 116mm
3,000m = 107mm
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7.5cm KwK42 L/70
Projectile weight: 7.2 kg PzGr.39/42 APCBC(HE)
Sectional Density: 1.280
Muzzle Velocity: 925 m/s
Total Kinetic Energy: 3080 KJ
Kinetic Energy pr. cm^2: 69.7 KJ
Performance against 90 degree 240 BHN RHA armour:
500m = 168mm
1,000m = 149mm
1,500m = 132mm
2,000m = 116mm
2,500m = 103mm
3,000m = 91mm
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8.8cm KwK36 FlaK18/36 L/56
Projectile weight: 10.2 kg PzGr.39-1 APCBC(HE)
Sectional Density: 1.317
Muzzle Velocity: 773 m/s
Total Kinetic Energy: 3107 KJ
Kinetic Energy pr. cm^2: 51.09 KJ
Performance against 90 degree 240 BHN RHA armour:
500m = 151mm
1,000m = 138mm
1,500m = 126mm
2,000m = 116mm
2,500m = 106mm
3,000m = 97mm
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7.5cm KwK40 L/48
Projectile weight: 6.8 kg PzGr.39 APCBC(HE)
Sectional Density: 1.208
Muzzle Velocity: 790 m/s
Total Kinetic Energy: 2122 KJ
Kinetic Energy pr. cm^2: 48.03 KJ
Performance against 90 degree 240 BHN RHA armour:
500m = 123mm
1,000m = 109mm
1,500m = 97mm
2,000m = 86mm
2,500m = 76mm
3,000m = 68mm
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5.7cm 6 pdr L/52
Projectile weight: 3.23 kg Mk.9T APCBC
Secional Density: 1.005
Muzzle Velocity: 831 m/s
Total Kinetic Energy: 1115 KJ
Kinetic Energy pr. cm^2: 43.69 KJ
Performance against 90 degree 240 BHN RHA armour:
500m = 103mm
1,000m = 90mm
1,500m = 78mm
2,000m = 68mm
2,500m = 60mm
3,000m = 52mm
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As most historians agree, it is pretty clear that when it came to armour armament, the Germans were ahead throughout the war.