Everyone knows it increase damage on 2 vet.
However, the increase in damage is not worth getting scattering increase.
5 explosives radius on 14 scatter means only 12.7% chance to hit target, and it has only 3 barrage rounds.
Obviously this means worse than before vet 2.
Scatter does not actually work like that.
Scattermaxdistance is not actually an indication of how mach the shell will miss but what is the upper limit of that value.
Now comparing that Scattermaxdistance does not help especially with weapon that have different ranges. Keep in mind that Pak howi has 160 range and the bigger the range the higher max should be.
If you want the actual linear deviation, you need angle_scatter that is calculated in the formula:
distance/tan(90-ANGLESCATTER/2)
If you want graphical representation of the scatter area check the following image.