JP Enterprises Gen 2 Silent Captured Heavy Recoil Buffer Spring Assembly for AR-10/LR-308

The JP Enterprises Gen 2 Silent Captured Heavy Recoil Buffer Spring Assembly for AR-10/LR-308 is a drop-in upgrade that transforms how your large-frame rifle cycles. Instead of the metallic clatter that comes standard with conventional buffer systems, JP's custom-ground captured spring and precision-engineered buffer work together to dramatically reduce friction, vibration, and that characteristic "spoon over a cheese grater" noise. This is especially valuable if you're running a short-barreled rifle, suppressed setup, or any piston gun where felt recoil and muzzle rise matter.

The Heavy version pairs a tungsten-and-steel weighted H2 buffer (approximately 4.7 oz total) with JP's proprietary spring design to deliver superior dampening across a wide range of shooter configurations. The aluminum guide rod keeps weight in check while maintaining the mass needed for proper bolt control. What makes this system truly versatile is that it fits both M4-style collapsible stocks and rifle-length buffer tubes—the included spacer lets you dial in the right setup for your platform without permanent modifications.

If your rifle's performance doesn't feel dialed in out of the box, JP offers auxiliary spring rate kits that let you fine-tune the system. This is especially useful for SBRs and suppressed rifles that sometimes need a different spring constant for optimal reliability and felt recoil management. The captured design keeps everything contained and eliminates the loose-spring rattle you get with traditional setups.

Key Features

• Drop-in captured spring system—no gunsmithing required
• Custom-ground spring paired with JP LMOS buffer for smooth, quiet operation
• Heavy H2 buffer with tungsten and steel weights (~4.7 oz) for superior dampening
• Aluminum guide rod reduces overall weight without sacrificing buffering mass
• Fits both M4-style collapsible and rifle-length buffer tubes (spacer included)
• Optimized for short-barrel rifles, suppressed firearms, and piston-operated guns
• Tunable via optional auxiliary spring rate kits for custom application

Specifications

Frequently Asked Questions

What buffer tube does this fit?

The Gen 2 Silent Captured Heavy works in both M4-style collapsible and rifle-length fixed buffer tubes. An included spacer allows you to use it in either configuration, so you don't need separate assemblies for different stock types.

Is this a true drop-in, or do I need a gunsmith?

It's a true drop-in system. No permanent modifications to your AR-10 are required—simply remove your old buffer and spring, install this assembly, and you're ready to shoot.

What makes the Heavy version different from a standard buffer?

The Heavy H2 buffer weighs approximately 4.7 oz and combines tungsten with steel weights for increased mass and superior recoil dampening. This is recommended for short-barrel rifles, suppressed firearms, and other setups where you need more buffering to control felt recoil and reduce cycling speed.

Can I tune the spring rate if my rifle doesn't feel right?

Yes. JP offers auxiliary spring rate kits that allow you to swap in a different spring constant and reassemble the captured system. This is particularly useful for rifles without adjustable gas blocks or for fine-tuning performance in specific builds.