Im trying to get wepon mastery as a challange and have pritty much got them all but stupidly left the pp till the end and i find it impossible to get even a single kill with, even in free for all. has anybody got any tips advice as im useless at using this gun
-Play Regicide
-Use an automatic weapon as your primary, preferably the storm rifle.
-Use dexterity so you can switch to the PP quickly after lowering your enemy’s shields with the storm rife.
-Try not to aimlessly wander around the map desperately trying to get kills with it as DMR and BR users will destroy you.
-If you are near two or more players who are in a firefight, their shields are likely to be low to none so use this to your advantage and try to finish some of them off while they are distracted.
-A lot of times there will be a player who is AFK in a regicide match so keep an eye out for those easy kills.
-Never try and kill an opponent with the PP’s charged shot.
-GOOD LUCK! 
Those are just some of my tips to complete the Plasma Pistol commendation so I hope they’re helpful to you.
Also, check out THIS thread for some more helpful tips.
awesome thanks dude ill give it a try