I was looking through the WFW M82A1 config, and found this:
class CfgRecoils
{
WFWBarret[]={0.022000,0,0,0.060000,0.014000,0.020000,0.050000,0.006000,0.060000,0.340000,0,0};
};
These values affect the recoil somehow. As I don't have experience making guns, I can't tell you what these values mean. The only suggestion I can give is to play with these values and see what they do.