Is the KKV bad or is it just me?

Everytime I use this thing it seems to get me killed and I kill the people using it. Last game I destroyed a guys green shield and damaged him some more I sprinted to him into a room, I switched to the kkv and began spraying him in the chest and I ended up losing the fight with me having a full blue shield and health, he was using a double tap. I use this thing at shotgun range as a destroyer I doge away from greyshields while shooting and I still get killed lol.

i have more instances of me dying with this thing but if I brought a d54 instead I think I would have won those fights