I have a Norica Dragon 177 , here in Spain.
I bought it a few years ago, but the heavy spring ( was shooting over 1300 f/sec) within Spanish law, made it hard to cock, and nasty to shoot.
I eventually stripped it down about a year ago, trial and error, eventually shortened the main spring by 35 mm.
Now , beautiful to shoot, at 10.6 foot pounds, easy to cock, and good enough to hole all shots at 38m, through a 40 mm circle with open sights.
Its now my favourite plinking tool and all round fun gun .
No work on the trigger, however , the lighter spring has made it overall much better too.
So far , about 5 tins of various pellets, not fussy at all.
Likes Gamo and BSA Elite , which suits me , at less than E4 a tin in the local hardware shop .