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 both M4-style collapsible stocks and also, using the included spacer, the longer tubes for fixed rifle stocks.
The H2 buffer is heavier than the standard spring. The buffer includes two Tungsten weights in addition to one steel weight. Weighing approximately 4.7 oz. Recommended for use in Short-barreled rifles, suppressed firearms, select fire rifles, and piston-operated rifles.
The Auxiliary Spring Rate Kits for the JP Silent Captured Spring allow custom tuning of the device to a given rifle. While the default spring offers the best performance for the widest range of configurations, a simple disassembly and reassembly of the JPSCS with a slightly different spring rate can yield truly optimized performance, particularly for rifles without an adjustable gas block.
The Heavy Spring System Version have Tungsten Weights and are recommended for Short-Barreled Rifles, Suppressed Weapons, Rifles with an H2/H3 Buffer, Select-Fire Rifles, and Piston-Operated Rifles.
Benefits of the Gen 2 Silent Captured Spring include:
New aluminum guide rod cuts overall weight
Heavier masses translate to more buffering mass and chance of bolt bounce
Full correspondence between SCS masses and H1, H2 and H3 buffers
Additional mass added to both AR-10 and 9mm models for better, broader function
Interchangeable buffers allow conversion between AR-15 and AR-10 models (and vice versa)
Includes spacer to allow for installation in both carbine-length and rifle-length buffer tubes.
Big Book Catalog, Issue:72, Page:040