Bri is spot on with his advice. One of the NEFTA HFT rounds (a few years ago) was won with a 3-9x40 scope with duplex ret. It had cost the owner £25.
He missed 2 shots - one a kneeler and the other a close 15mm reducer because he gave it the 10 yard aimpoint when it was closer to 13 yards. If the shooter had known the rules he would have known the target could not have been closer than 12 yards (NEFTA rule) and the shooter wobbled on the kneeler.
The scope would have cleared the course if the shooter had been up to it - he was the weak link.
He is also right about getting over to Emley and tracking down Chris - he has put more effort into helping new shooters than any other shooter I know and he knows his stuff