Not entirely sure how it affects things, but weapons with very low recoil, like the Adamant Laser Cannon and Future Police Rifle have ridiculous accuracy. At close and long range, with or without scope.
So, I guess that answers it. Although, for single shots, it makes no difference AFAIK. But when combined with a very high rate of fire, it makes a ton of difference! My Champion Peacemaker has medium recoil, but is close to useless in some situations where the FPR is a straight up killer!