Which one are you talking about?
I tried 5.6 Wasps in my Webley & Scott Hurricane (same as Tempest but with slightly longer barrel) and they were so good I ended up putting them through my rifle.
On the other hand it LOVES the Dynamic Sn2 pellets and gets by on most good lead pellets like AA field or Bisley supe field. So it looks like you need a test pack from one of the suppliers to work it out for your individual gun.
If you are talking about the Chinese version I have no idea.