FWIW I'm a big fan of a simple arrangement of a hook, thin wire, pulley or crank, half an hour's metal bashing, a few 12 bore blanks and one of these or similar https://www.ebay.co.uk/itm/265149062590?hash=item3dbc1d9dbe:g:vpYAAOSwvoJgkkoz&amdata=enc%3AAQAHAAAAoJ2zx3eY7YFbD0hFFSbBRWVXIOdjsvwZqvWUE5iLJLIKam6%2BWO8%2BeZesOU2lBBonWIBYcItkHCls%2BoQO7pcNx6M6SPMgB6ss4Msn79eNTtbYS9oi6ay5teyNyY4j%2BgQiKN3DqCwjOBP0OGsQyS7gMbyAQUR5Wq%2BDaKoLs52vr8MM4rpE6MdTbn4S476JzOKNQyhxyQ4JTmxT70mHS45885c%3D|tkp%3ABk9SR66IufTbYA
Worked a treat the only time it was ever tested for real. Matey abandoned his plans and buggered off PDQ, half the neighbourhood woke up, and one of them hit 999 to report gunshots (plural, although there was only the one) 🙂