Most over/under shotguns let you select which barrel fires first. It’s an important feature because you should select the bottom barrel to fire first because that’s the barrel that gives you the most straight-back recoil so there’s less recovery necessary for the follow-up shot. A reason you’d switch to the top barrel to fire first would be some unusual circumstance like having fixed chokes, the tighter one on top, and ducks you thought would decoy in only offering farther passing shots.
Conveniently, many modern over-under shotgun barrel selectors are marked “U” so you know the “under” barrel is selected, or “O” for the “over” barrel. Then there are those shotguns with the dot codes and I could never remember whether the single or the double dot was the over or the under barrel. Then I read an easy way to remember was to think of a woman. The adjacent infographic should be self-explanatory and always help you remember top from bottom and over from under.
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