G&G Scar L upgrade suggestions?

[MikeLondon]

Hi
Had my stock Scar L for some time and trying to get some improved range and accuracy from it. Recently replaced the hop rubber with a mad bull blue but didn't really make any difference. Have a spare TM and Systema rubber but not tried either yet. As far as I know the barrel is already a tight bore? So didn't see much point putting a new one in. Interested what mods other owners have done to get the best performance? Particularly which hop rubber gave the best result with the stock hub and nub. Cheers