A subjective area Bill. Shooting well involves both mental and physical discipline. Some days you are ON, others not so much. You are correct with "practice" though, there is no substitute. As soon as you stop practicing your skills tend to gradually begin slipping away, to keep your hand in you need to keep at it. If it is possible find someone who is an accomplished shooter and is willing to coach you. Another's eye always helps pick out the little things that lead to better shot placement and aid in finding problem areas you need to work on. An example would be flinching. Some areas to concentrate on are:
Body Position: Is the rifle pointing naturally at the target area once you position yourself to shoot? If not adjust your position until it is. Do not force this or pretzel yourself here, you should feel "right" and natural once in position and feel no muscle strain and the gun pointing generally at the target so that it only has to move slightly to line up vertically.
Breathing (very important): Once in position, with the muzzle in line with the target, a normal, natural, breath should see the muzzle lower until it is slightly below the target. Hold the breath there and clear your mind while allowing air to escape until the sights aline with the target. Relax that grip, muscles all balled up help nothing here. That extra cup of coffee didn't help either.
Trigger Release: Incrementally, smoothly, pull back on the trigger (just close your hand actually) and release the shot - then freeze for a moment, relax, and "call" your shot - mentally picture where it hit before you look. You will get very good at this eventually. Check the shot, ask yourself what went wrong, what went right and what would improve things. If you are getting good groups you are doing well whether they are hitting the bullseye or not. you can always move the point of impact by adjusting things such as sights, body position, breathing and trigger work.
Pretty basic I know, but mastering the basics leads to better shooting. Break the elements, the act, of shooting down (here is where another person can help) into individual movements and stages, once you have a good sequence stick with it unless you can improve it. The clear air of mornings are generally the best times to shoot, before the sun gets up and causes heat waves. If you are having a less than good day go do something else, do not force it, it won't get better that day.
Have fun, be safe and enjoy.
dave