No officer. Simple barrage.
Many may not be correct but this is perfectly fine since vet 3 hit all shells inside smaller circle, while vet 2 is way more inaccurate.
There are tons of things that affect scatter like LoS as well. RNG may have just blessed you with 1 barrage, who the hell knows. But I put my faith in numbers and statistics instead of screen shots of literally 2 artillery barrages compared.
The only difference between vet 0 and vet 3 is the distance ratio, meaning that shells are always just as accurate as they always were but the amount they can deviate from the barrage is smaller. This means you will miss your target just as often as you always did, but by a smaller margin.
Scatter angle:
9.25
Min tilt angle:
0.0
Distance obj hit min:
0.0
Distance offset:
0.0
Fow angle multi:
1.25
Tilt max distance:
0.0
Tilt scatter chance:
0.0
Distance ratio:
0.074
Burst pattern:
false
Max tilt angle:
0.0
Delay bracket change chance:
0.0
Distance max:
18.5
Fow distance multi:
1.25
Scatter angle:
9.25
Min tilt angle:
0.0
Distance obj hit min:
0.0
Distance offset:
0.0
Fow angle multi:
1.25
Tilt max distance:
0.0
Tilt scatter chance:
0.0
Distance ratio:
0.0556
Burst pattern:
false
Max tilt angle:
0.0
Delay bracket change chance:
0.0
Distance max:
18.5
Fow distance multi:
1.25
Those distance ratios? Exactly the same on the ML-20. Meaning the ML-20 will always be just as accuarate as you are but doing more damage
EDIT: Also why did you hide your playercard?