Hello Paul, the cartridge on the left is a 5.44 mm Zielmunition Hartmann “A” or “long version” for shooting distances up to 150 metres and loaded with black powder. It was made for a subcaliber device developed in Argentina in 1909 by Federico Hartmann and used with 7,65 x 54 Mauser Model 1891 carbines and rifles. Several schools also used these devices for shooting exercices. There is also a rarer short version designated “B” and loaded with smokeless powder for distances up to 25 metres.
Another subcaliber device was designed for 9 mm Luger pistols but it only chambers .22 Short ammunition (Hartmann ammunition has a wider and thicker rim).
These steel adapter cartridges are very rare and were made of steel (9 mm & 7.65 x 54) or steel/brass (7.65 x 54) and marked “Schuchardt u. Schütte Berlin Patent Hartmann”. The ammunition was made for Schuchardt & Schütte by RWS and packed in 100 round boxes written in German language. The headstamp logo with three concentric circles was the trademark of “Zielmunition Hartmann”.