The CH-003 bullet was a light projectile intended for a reduced recoil cartridge in 7,62 x 51 mm caliber. It was developed at CETME by the german engineer Dr. Gunther Voss, who settled in Spain after WWII.
CH-003 means Cobre-Hierro Nº 3 (Copper-iron number 3). It weighs 5,5 grams (85 grains). Muzzle velocity was 760 m/s.
The bullet shape on the cartridge is very similar to that of the mass-loaded CSP-003, but it is attracted by a magnet because of the iron core.
Here are three CETME cartridges:
CSP-003 (lead rear core, plastic front core)
CH-003 (iron core with empty rear and tip)
CAH-003 (rear iron core, aluminum front core)