Yellow Buffer Spring manufactured by Sprinco USA
 
This is a MUST for proper function in 300BLK
 
We have tested this spring THOROUGHLY and it is our favorite for virtually all our platforms.
 
YES, that includes 5.56/.223
 
We have found this spring assists with felt recoil, ease of use and reliability for low pressure systems without hindering function.
 
We recommend pairing the Sprinco Yellow with the JP Enhanced Gas Ring for improved function.
 
WARNING: This spring will only function with the use of standard mil-spec 7.25” long ar15 carbine buffer tubes with standard “m4/carbine” style buffers.