The Gen 2 Drop-in captured-spring recoil system helps your AR function more smoothly and quieter without any permanent modifications. The carefully balanced, custom-ground buffer spring, combined with the JP LMOS buffer, greatly reduces friction and vibration - say goodbye to the annoying “spoon over a cheese grater” noise of conventional springs and buffers. Fits buffer tubes for M4-style collapsible stocks.
The one certain requirement for function is a 9mm bolt with an open central channel through which the guide rod of the SCS unit can pass while cycling. If the nonbolt face end of your bolt assembly is not hollow, the SCS is not compatible. Some 9mm bolts have a separate mass that can be removed, but others are a solid piece that cannot be modified to allow function. Certain other 9mm bolt models such as the Bushmaster also have removable masses, but the removal of the mass leaves the overall length of the bolt shorter and hence non-functional. Make certain of your bolt before purchasing and installing.
Benefits of the Gen 2 Silent Capture Spring include:
New aluminum guide rod cuts overall weight
Heavier masses translate to more buffering mass and chance of bolt bounce
Additional mass added to both AR-10 and 9mm models for better, broader function
Big Book Catalog, Issue:72, Page:040