Welcome to the AGN forum.
It sounds like the distances you need for the type of shooting you are doing are between 10 to 55 yards, try sighting the rifle at 25 to 28 yards and use holdover. Practice your holdover and windage and get comfortable with your scope. You will need more yardage to practice for the distances needed in your type of shooting, you can practice your "short game", from 10 to 30 yards and then go to a location for the farther distances. I like to do a work up from 10 to 60 yards, and then I shoot random yardage. Also try placing the targets at different heights from the ground to higher elevations this will help you to dial in parallax. If you are not using reactive targets I would suggest getting some, they will make a difference in your practice, and get you used to the different target sizes or kill zones as they are called. Air venturi makes some that are price reasonable. I sight in on paper then go for the reactive targets. Make sure that you review the rules for the type of field target you plan to shoot, and set your rifle up accordingly, and practice to the requirements needed for your discipline, that way you don't pickup bad habits or have your gun set up incorrectly to the rules. I was practicing with a bipod attached to my rifle (not allowed) I took it off and had to get used to the weight change. I would also recommend that you attend the same type match you plan to compete in, and see what it's like, the equipment others are using, and how the match is conducted. After that I think you will be able to practice more effectively for your type of matches and have the confidence/knowledge in what you are doing. Don't forget to have fun and enjoy your journey. Please keep me posted on your results.
TODD