NAME – 15.6x70mmR (20 Gauge 2 ¾ Inch) # 7 ½ Shot

TYPE – Shotgun shell

YEAR OF INTRODUCTION – 1890’s

COUNTRY OF ORIGIN – Great Britain

CASE TYPE – Rimmed straight

CARTRIDGE LENGTH – 6.22 cm (2.45 in)

CASING LENGTH – 7 cm (2.75 in)

CASE HEAD DIAMETER – 17.58 mm (0.692 in)

CASE RIM DIAMETER – 19.33 mm (0.761 in)

LOAD – #7 ½ Lead Shot

LOAD WEIGHT – 28.4 g (1.0 oz – 437.5 grains)

PELLET DIAMETER – 2.41 mm (0.095 in)

NUMBER OF PELLETS – 350

WEIGHT OF PELLET – 0.081 g (1.25 grains)

TOTAL ROUND WEIGHT – 38.4 g (1.35 oz)

MUZZLE VELOCITY – 372 m/s (1220 fps)

NOMINAL BARREL LENGTH – 66 cm (26 in)

MUZZLE ENERGY – 1961 j (1446 ft/lb)

MUZZLE ENERGY PER PELLET – 5.62 j (4.13 ft/lb)

15 fps/in per 2 inchs bbl length from nominal