7.62x54mm R

Its a rimmed rifle round designed by Russia to be introduced in 1891.
   It was orignaly designed for Russian Mosin-Nagant rifle. It is one of the only few rimmed cartridges that are still in service, and it has a history of longest service record then all other rimmed cartridges. 

Different models of Bullets

Including FMJ, Tracer, AP, Hollow point

 This bullet is still in used in Russian Dragunov Sniper rifle, as well as some modern machine guns like PKM.

 To increase accuracy of soviet Dragunov SVD, Russia developed 7N1 rounds which greatly increases its ballistic co-efficient.

Performance:
  Its ballistic performance is slightly better then 7.62x51mm NATO rounds. Its muzzle velocity is comparable to .308 Winchester bullet. The spritzer shaped bullets used in military variants have particularly elongated shape which provides a favourable ballistic co-efficient and sectional density contributing to long range attacks. 

Bullet dimensions.