5.56 Linked 4:1 (4Ball & 1 Tracer)

Projectile SS109/M855
Material:  Jacket – Tombac (CuZn10),
Core 1 — Lead antimony, Core 2 – Steel
Weight:  ~4.00 g / 62 gr
 Length: 23.4 mm
Propelling charge: Spherical Powder

Tracer M856
Material:  Jacket – Tombac (CuZn10),
Core 1 — Lead antimony, Tracer – Tracer comp
Weight:  ~3.92 g / 61 gr
 Length: 28.45 mm
Propelling charge: Spherical Powder

Packing 

200 rounds in metal link belt (M27)

4 metal link belts in metal box M2A1 (800 rounds)

2 metal boxes wire bound wooden box (1600 rounds)