Are the Elimination Counts Bugged?

Just a quick question. When we look at our loadouts, I notice that the number of eliminations listed for each gun seems extreeeeemely low, even for me. I am not a great player, but I'm better than my kill count per gun would have you believe. I only ask because I had a challenge to get 50 hip fire kills, and I used my PPSH. This was for the entire challenge, bc I wanted to get it done fast. Yet, when I look at my total eliminations, it only shows me having 39 kills with the damn thing. Is this a "me" thing?