you need to get onto a 30yrd range or a field and get a target out to 30 yrd to zero you might find that because your so close that you would need hold over due to the pellet being on its way up but not reached its peak,it depends what your rifle is pushing ftlbs wise and what weight of pellets your using ,when you know these figurs you can calculate your 2 zero point,s one might be 10yrd and the other 30yrd,but if you have access to a chrono download chairgun and you can do the maths and find out if your scope needs more shims or less or maybee lower mounts