I had a Panther(?) air pistol, like most kidas when I was a boy – an awful weakly luger-styled gun. You could shoot in the air and watch the pellet arcing downwards! A lucky few had the Webley with teh short barrel that pivoted at the front. That was really nice to use.
Though i say it myself I've always been a decent shot with airgun or simple (as againmst compound) bow. Targets only, aside from that rat plague a few years ago, which caused my brother to send me the Crosman!
I got much mocked by the family for bragging about my skills until I shot out a candle flame at 10 yards on the first shot. that was leaning on a support and with a scope though. Some of the shine came off when my 12 year old daughter succeded on her second try 
That temperature difference explains why I have to reset the sights each time I use it! It seems to be reasonably consistent until you get to the very dregs of the bulb though. Problem is you don't notice the drop in power, you just start missing!
Neil