have a pop at (someone or something)
1. To physically strike someone or attempt to do so. Primarily heard in UK. Stay away from that rival gang—those guys will definitely have a pop at you.
2. To criticize, judge, or disapprove of someone. Primarily heard in UK. My parents had a pop at me for my decision to study art in college, instead of law or medicine. I just know my boss is going to have a pop at me for that accounting error I made last week.
3. To try to do something. Primarily heard in UK. A: "Do you want to try driving my car, to see how you like it?" B: "Yeah, sure, I'll have a pop at it."