Finally nailed it! - I'm so happy I can hardly hold my water
...after a long wait since 3/3-2020 I really wanted this gun to perform as I hoped it would, surely did not expect a semi to mach a single shot in accuracy, but now I see it may even match my beloved hair triggered Leshiy Classic
Please note, this is MY version of the L2 and yours may shoot just fine
Could not get this gun to perform with any type of pellets, had lots of horizontal stringing
After seeing how well it shot when single loading in the barrel direct I know the barrel was fine..and my trigger control was OK
The line up and indexing of magazine to barrel is perfect! - you can check that yourself if you mount the mag without the cover plate and look down the barrel with light on white paper as background, so nothing wrong there
The edge at the throat of the barrel on my version was really sharp, should not matter as the diameter of the outgoing side of mag is less than the throat of the barrel but to take out this variable I did polish it ever so slightly in the lath using fine metal abrasive on a wood dowel
(picture is before polishing)
Made no difference - so barrel perfect, line up and index of mag perfect, then why the stringing when shooting through the mag, what was the difference? - well opening and closing the breech for every shot of cause!
So I tried just that and what a difference that made - so the locking pin dunnit - was moving up a bit with every shot - opening and closing the breech would reset the pin
So the cure is a stronger spring
Take a look at the target shot from 35 yards
Upper right 4 x 8 shot from mag in one go, notice the 1 far left in each group, that's the first shot
down midst 2 x 8 shot single loaded in barrel, point of impact is slightly lower, single loading in the barrel reduce the velocity by 2-3 m/sec
upper left 2 x 8 shot from mag with breech opened and closed for each shot
Happy days!