A5 Assembly Buffer System - Buffer A5 H2 KAK

The A5 Buffer Assembly is an advanced buffer system designed to significantly reduce felt recoil, eliminate bolt bounce, and provide exceptional reliability and consistency throughout the AR-15 operating cycle. This version features the A5 H2 KAK buffer with an additional mechanical bumper and flat-wire spring.

In short, in our own words: the rifle operates more smoothly and linearly, making it easier to control, so you can shoot faster and more accurately. Simple. In our opinion, this is the best mechanical recoil-reduction system for AR-15 rifles, without directly affecting reliability or the gas system.

WHAT IT DOES:

Recoil Reduction – Significantly reduces felt recoil without compromising reliability or smooth cycling, as can be the case with hydraulic buffers.

Smoother Operation – The use of a longer rifle-length spring combined with the optimally weighted H2 buffer optimizes the operating pressure within the rifle, particularly in Carbine and Mid-Length configurations. This results in a smoother, more linear operating cycle. It noticeably improves the overall shooting characteristics of the rifle and allows for better control and accuracy without sacrificing reliability.

High Consistency and Reliability – Provides a more consistent bolt carrier velocity, directly contributing to improved accuracy, shot-to-shot consistency, and tighter groups.

Bolt Bounce Elimination – The system effectively reduces bolt carrier bounce against the barrel extension, ensuring secure and reliable bolt lockup during sustained fire.

THE COMPLETE KIT INCLUDES:

Extended Stock Tube (Buffer Tube / Receiver Extension): Made from durable 7076-T6 aircraft-grade aluminum and featuring 8-position adjustment. It is approximately 3/4" longer than a standard carbine buffer tube, bringing the operating characteristics of the system closer to those of a full-size M16 rifle.

Long Flat-Wire Recoil Spring: A spring with a higher number of coils than a standard A5 spring, thanks to the use of flat wire. This further improves the smoothness of operation and helps reduce felt recoil.

A5 H2 KAK Buffer: Unlike a standard AR-15 buffer, it is longer and contains four weights instead of three. In the H2 version, two out of the four weights are made of tungsten, for a total weight of approximately 5.6 oz. This change results in a smoother and more reliable operating cycle. It reduces felt recoil and eliminates bolt bounce during sustained fire. The KAK version features an additional spring-loaded bumper that further reduces felt recoil. The bumper is fully mechanical rather than hydraulic, providing reliable and consistent operation under varying environmental conditions without affecting firearm reliability.

Castle Nut: A solid locking nut securing the stock tube, made from stainless steel to stringent Mil-Spec standards.

QD End Plate: A durable mounting plate featuring an integrated Quick Detach (QD) socket, allowing a sling to be attached to the rifle quickly and securely.

INSTALLATION INFORMATION

The kit is fully compatible with standard Mil-Spec lower receivers. Due to the increased length of the A5-style tube (approximately 3/4" longer than a standard carbine tube), some adjustable stocks may not sit directly against the castle nut when fully collapsed.

Installation is simpler than you might expect, although experience and the appropriate tools are recommended. If you have any doubts after reviewing the instructions, contact a reputable gunsmith or reach out to us directly. We are happy to help.

NOTE: Due to the cutout in the KAK buffer around the bumper and the use of a flat-wire spring, the KAK version requires a little more patience when inserting the buffer into the tube. We recommend using a small tool to press down on the buffer retainer pin while inserting the recoil assembly into the buffer tube.