Sure you can hit things with it but like with everything else I'd practice on a non-live target first. 20mm objective lens isn't going to be greatest, for letting light in, so your results will be solely dependant on your abilities as a shooter.
Alot of companies do 1.5 mag x 20mm scopes. Optic quality varies with price, as a rule.
The main thing is that you have to be able to see it to hit it. Magnification helps but the quality of the scope plays a huge part. If you've got a cheap Hawke, or Simmons, scope it's not going compare to a Leupold or a Swarovski.