SV-98 loses 40% of its damage with red laser

Quite simply the SV-98 loses 40% of its damage when the 5mw red laser is equipped.
I hadn't noticed it when I equipped it at first, but started to wonder why I was getting 50 damage hits in matches at quite substantial ranges where "sweet spot" should have activated as well.

Other lasers don't do this, and it doesn't happen on other guns either (that I've found yet at least), only 40% reduction on the SV-98.

Surely this cannot be intended? Doesn't make any sense for that one gun to be irrationally punished vs all other weapons in the game.