I have numerous videos of being out gunned carrying an AK by the K30 at 50m+. I mean I land the first shot and still get beat. Here's what Battlefield Wiki says about it:
The K30 is a very fast firing submachine gun, capable of shredding targets at close range, while losing effectiveness over range more aggressively compared to other submachine guns. This weapon has high recoil, high spread and low damage.
It's not very "High spread and low damage". I own a semi-auto one of these, (Kriss Vector) and fired the full auto version. I can tell you that at 25m, you have a hard time hitting a human torso really accurately. Not saying it should be that hard in BF, but outgunning an AK at 50 - 100m, nah B.