its kinda a weird gun in that it has a very diff click rate making it easier to jam. for that u can only just practice with it.
try to strafe as much as u can when firing otherwise use cover when possible. popping out of corners with every shot is also very effective at close range
as for range up to 40m u are pretty accurate hipfiring unless u get unlucky with rng - u can use it for longer ranges but rng might fuck u off or u just wont deal enough dmg.
for mods id recommend rs3 or any purple except for mobsling - ir3 is a must
u need to put time on it, its a very very strong wep once u get used to it
~3k hrs with oscar
