A telescopic recoil system for a firearm having a receiver and a bolt carrier includes a recoil system base, an axle fixed to the base, a central buffer tube slidably mounted on the axle, an axle buffer spring between the base and central buffer tube, biasing the central buffer tube away from the base, an outer tube slidably mounted on a forward portion of the central buffer tube, a spring buffer tube slidably mounted on a rearward portion of the central buffer tube, a rear buffer spring between the base and spring buffer tube, biasing the spring buffer tube away from the base, a central spring between the spring buffer tube and outer tube, biasing the outer tube away from the spring buffer tube and away from the base and an exchangeable spring between the outer tube and the bolt carrier, biasing the outer tube away from the bolt carrier.