At a recent Appleseed, one student had trouble firing all ten rounds within the time limit on Stages 2 (seated rapid-fire) and 3 (prone rapid-fire). He was using a scoped 10/22 with an unmodified bolt release, and he is left-handed. He could not operate the bolt release one-handed because of the scope, and with his right arm slung up, two-handed operation was awkward and time-consuming. He was taking over 20 seconds to fire his first shot.
The cause of his problem: he was locking the bolt back at the end of his preparation period. So when he got into position and inserted the magazine, he had to operate the bolt release to close the bolt.
Appleseed rules do not require that the bolt be open in the transitions on Stages 2 and 3; just that safeties be ON and rifles unloaded (mags are on the mat). By leaving the bolt closed upon standing, you can simply rack the bolt once you are in position and loaded.
CMP Rimfire Sporter rules make the bolt release a moot point. In CMP the commands are: “ON THE FIRING LINE STAND…WITH ACTIONS OPEN OR CLOSED ON EMPTY CHAMBERS…LOAD FIVE ROUNDS.” (The “Actions Open” is for manually-operated rifles.) You insert the magazine with the bolt closed. After inserting the mag, you may not cycle the action of your rifle. Upon the START command, you drop into position with the rifle loaded but no round chambered, and then you rack the bolt.
For us lefties with scopes, rotate the rifle counterclockwise with your support hand so the bolt handle is on top, and use your left hand to cycle the bolt. This way you don’t have to reach over the scope, and your support arm doesn’t leave your carefully built NPOA position.