From: http://www.russianarms.ru/forum/index.php?topic=10173.0 (Google translate)
Photos posted by "bar5428"
The two fuzes on the left are made from recycled 7.62x54mmR cartridge cases,
Simplified fuse sleeve UVG mod. No. 1 (Google translation) or Упрощенный взрыватель гильзовый УВГ обр. №1
From: http://saper.isnet.ru/history/istor-muv.html (Google translate, view this webpage for more detailed information)
Generic diagrams showing the components of the cartridge case fuze-
“Simplified fuse. Its device is extremely simple. It consists of the following parts - sleeve (or recycled cartridge case) (1), hammer (striker) (2), spring (3), capsule holder (4), P-shaped combat pin (5) and safety pin (6).”
In the photo below are several versions of the fuze, the cartridge case version is shown on the right and the screw in igniter (capsule holder as shown above) is shown just below the cartridge case