Hi y'all. I am new to air rifles, I'm a semi auto shotgun user but due to a very short and limited hunting season here in spain on designated hunting grounds, namely october to february and only on thursdays, saturdays, sundays and public holidays, Having permission on quite a lot of private land, and in order to not attract the attention of the authorities I decided to buy an air rifle, I bought a Hatsan 6.35 calibre (.25 in old money) 24 joules breakbarrel, scope, sound moderater etc. In the UK being over the legal limit of 16.7 joules this would require a full firearms licence. Anyway my point, is there any way to 'Tune it up', example get more power from it than the 24 joules it already produces..? It does feel powerful already and can stick a solid open point slug a good inch into a builders plank from around 40 yards, but would just like a bit more from it.