Orly? Cool! Here, I'll show you. You had:
AddDamageType("explosiveshotgun", '<bitmap:add-ons/Weapon_ExplosiveShotgun/CI_expshotgun> %1', '%2 <bitmap:add-ons/Weapon_ExplosiveShotgun/CI_shotgun> %1',0.5,1);
datablock ProjectileData(explosiveshotgunProjectile)
but I changed: AddDamageType("explosiveshotgun", '<bitmap:add-ons/Weapon_ExplosiveShotgun/CI_expshotgun> %1', '%2 <bitmap:add-ons/Weapon_ExplosiveShotgun/CI_shotgun> %1',0.5,1);
datablock ProjectileData(shotgunProjectile)