The dummy grenade cartridges in my collection have “GW MANIP TREIB-PAT” rolled into the brass near the base. There was a special magazine for the grenade cartridge which was shorter internally so standard length rounds would not fit.
All of the blunter ogive brass dummies, number 3 from the left in your photo, that I have examined appear to be modified from the standard ogive dummies. The point of the bullet has been turned off at a later date, the brass has less aging tarnish and the machining is not quite concentric with the original machining. Perhaps these were made to produce an “universal” dummy which would fit both magazine types. It has also been suggested that the tip of the bullet was turned off because they got battered in use and this modification (at the factory) made them more durable.
Both of the shorter dummy rounds are supplied in red painted, fibre board, chargers with a wood nose strip to prevent longer rounds being used. They also have a “window” in the left side through which the necks and bullets can be seen. The standard length dummies came in a red painted charger without either the wood filler or the window. There was no charger for live Grenade cartridges.