I think it is a case of knowing youre gun as they are all different. Basically clean it if you know the groups are opening up, shoot from a rest to eliminate pilot error.
P70FT less tha once a year just to be sure, dosent realy need that though.
Anschutz 2002 FT Regularly when groups open up.
Steyr Lg110 Every 2-300 shots. A pul through after shooting helps extend this to 500-1000 shots. Once the barel had had 4-5000 through it, needed less cleaning
Steyr LG100 very rarely, once a season. Probably the barel was shot in well before I got it.
Make every shot count
Steyr Hunting 5 Scott Lupold 3-9x33EFR(for LSR )
FWB P70/Bushnell 6500 4-30x50T
SteyrLG110/Bushnell 6500 5-30x50
Steyr LG 100 FT Bush elliot 8-32x40