My one shot groups are fantastic...
Seriously though, my LG110 will shoot a 13mm wide 10 shot group at 50m, none of my other pcp's will. (HW100, AA510, BSA R10, Walther domi, Daystate renagade)
To do it, it needs just the right batch and die number of JSB's, a totally still day (which is almost never) and a lot of luck, as there are lots of variables beyond the control of the shooter that will spoil the group. The more shots in a group, the higher the chances are of a 'flyer'.
Anyone who thinks they can shoot 5p groups at 50m all day, is having a laugh... If that was true, I'd like to see a 500 shot group inside a 5p!
I think a 50p size group at 50m is about the norm for rested shooting of sub 12 pcp's. Defo not rubbish, any working pcp should be able to do that day in, day out, on a calm day.
(has anyone watched Kirsten Joy Weiss shoot an egg with a 10/22 at 300 yards standing? Took a few shots but jeez...)