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JG9 LRBHO Actuator Kit

9mm Actuator Lower Parts Included:
4140 Steel Ejector
Steel LRBHO Actuator
Roll Pin
Lightened Bolt Catch Spring
Allen Wrench
Threaded Bolt Catch Screw


Please watch installation video on how to install JG LRBHO

The last round bolt hold open feature on a standard AR-15 is a simple bolt catch release that incorporates the standard action and functions of any AR-15 lower receiver. When switching calibers to the 9mm in the AR platform, the word AR is about the only thing similar. Due to the size of the round itself, the magazine differences and overall function of the 9mm round, when switching over to the AR-9 platform from the AR-15, the change from gas operation to blowback operation, buffer weights and barrel lengths, are just a few of the numerous differences that occur between the two designs. Jacob Grey Firearms tries to make this transition and process a little easier and user friendly with their LRBHO feature on their JG-9 upper and lower receivers. All our parts are tested under the harshest conditions using a variety of different bullet weights, barrel lengths, suppressed fire, unsuppressed fire, hot and cold temperatures. The result being a reliable, continuous cycling AR-9 pistol or rifle that keeps the bolt open on the last round fired each and every time.
** Make sure the lower receiver has our lightened bolt catch spring installed. If you purchased one of our complete firearms it came preinstalled. If you purchased one of our lower receivers or receiver sets, this spring was included in the small bag located inside the receiver box.

***Please note using too heavy of a buffer or too powerful of a spring may cause the last round bolt hold open to become inoperable.

****Please see our buffer weights and spring recommendations on our website for additional information.

No attribute set

No attribute set

Standard Equipment

No standard equipment set

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