It mainly depends in the range you hit your target from.
Short range: 25~29
Middle range: 22~26
Long range: 17~23
The PKM has nasty sights that blocks out a large portion of your screen compared to the MG3, making it hard to see whats happening around you.
It's extremly effective from short to long ranges due to the PKM's little recoil making ot easy to kill at a range, it is accurate in any range and still maintains its accuracy somewhat in the longer ranges making it a good LMG to snipe with. The downside is that this is not a good CQC weapon to use due to its lowered Rate of Fire compared to the MG3 and for the most part SMGs, Shotguns will indefinitely outgun you.
This weapon has 100 round Belt with another 300 rounds in reserve. This gun has a reload time of 7.3 seconds.