For this kind of experiment, do you even need a scope? (Asking as a complete noob). It seems what you need most of all, is the ability to make the most minute

For this kind of experiment, do you even need a scope? (Asking as a complete noob). It seems what you need most of all, is the ability to make the most minute of adjustments to the aim of the rifle, combined with feedback on where the last bullet landed relative to the target. Then it becomes a bit like Newton-Raphson approximation. Or are the conditions on the record such that each successive firing must aim from scratch? One question of interest is how far repeated shots with the exact same rifle aim are going to land from each other. That would depend on changing wind directions and other atmospheric effects. Presumably you pick a day of near zero winds for such attempts.