The Deeley and Edge forend on my 1896 Clabrough sidelock ten bore won’t come off. The lever only lifts partway and doesn’t disengage from the hook, even if I put quite a bit of pressure on it and pry the forend from the barrel gently with half a safety pin. This gun has Harrison ejectors, and when I pull the triggers I can feel the left one firing but not the right; shells are extracted but not ejected from either chamber. The ejectors were working before the forend problem occurred.

Any advice on what to try next? Thanks very much.