5.6×57mmR

5.6×57mmR
Type	Rifle
Place of origin	Germany
Specifications
Case type	Rimmed
Bullet diameter	5.56 mm (.224")
Neck diameter	.379 in (9.6 mm)

The 5.6×57mmR cartridge was created by Rheinisch-Westfälische Sprengstoffwerke (RWS) in Germany for hunting small deer. There are no dimensional or ballistic differences between the 5.6×57mmR round and the 5.6×57mm round (q.v.) other than that the former is rimmed.

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Wikipedia