Basic : CCI Standard, CCI Subsonic
Mid : Eley Sport (green box)
Top : Lapua Polar Biathlon, Eley Tenex, Eley Black
In general the slower 22 ammo is better, just over supersonic seems to be the sweetspot
For target ammo talk to your local smallbore club, they will know where to get it. Belmont does SK and Lapua.
Other suppliers to check with : TSNZ (Target Shooting NZ), and also ShootingStuff
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