What is a Sprinco 5-Coil?

Sprinco AR-15 Extractor Springs are made from high quality Chrome Silicon wire stock that has been heat treated, stress relieved, and cryogenically processed to produce long lasting durability. 5-Coil springs provide a higher spring pressure than OEM springs for use in all AR-15 pattern rifles and performs well even if the rifle is dirty.

What does Chrome Lined mean?

Chrome lining is a treatment applied to the inside of SIONICS barrels. Chrome lining is essentially an alternative to a Melonite/nitride finish. During this process, chrome is applied to the lands and grooves of the barrel’s rifling, as well as the chamber. In order to ensure accuracy with this extra material, chrome-lined barrels are typically bored out more than the…