Functional Description: Three-Round Burst 

The functional check of the three-round burst is as follows:
(assume that the weapon is fully loaded with a live round in the chamber and the selector lever on BURST)

Hammer is cocked.
Front hook of burst disconnector is in stop notch.
Trigger is pulled.
Trigger nose drops and hammer falls firing the first round.
Front hook of burst disconnector holds burst cam in place as hammer falls.

(NOTE: Anytime the hammer falls forward, the clutch spring releases the burst cam and allows the front hook of the burst disconnector to keep it in place.)

As the bolt carrier assembly moves to the rear, the hammer is forced to the rear.
The clutch spring of the burst cam clutches the cam and causes it to rotate one notch as the hammer is forced back.
When hammer is fully to the rear, the automatic sear catches it.
The front hook of the burst disconnector in now fully in the second notch.
As the bolt carrier assembly travels forward, the automatic sear releases the hammer and the hammer falls.
When the hammer falls, the second round is fired.
As the bolt carrier assembly moves to the rear, the hammer is forced back to the rear.
The clutch spring of the burst cam clutches against the cam and causes it to rotate one notch as the hammer is forced back.
When the hammer is fully to the rear, the automatic sear catches it.
The front hook of the burst disconnector is now fully in the third notch.
As the bolt carrier assembly travels forward, the automatic sear releases the hammer and the hammer falls.
When the hammer falls, the third round is fired.
As the bolt carrier moves to the rear, the hammer is forced back to the rear.
The clutch spring of the burst cam clutches against the cam and causes it to rotate one notch as the hammer is forced back.
When the hammer is fully to the rear, it is initially caught by the automatic sear. However, the front hook of the burst disconnector is now fully in the next stop notch which is deeper than the others.
Because a stop notch is deeper than the others, it allows the fron hook of the burst disconnector to further forward than before. This allows the rear hook of the burst disconnector to latch on the rear hammer notch. This holds the hammer fully to the rear even though the trigger is still to the rear. This happens when the burst is over and the firing is stopped.
Once the trigger is released, the triger nose comes up and holds the hammer back.

(NOTE: Pulling the trigger to the rear and holding it back again will fire another three-round burst. This will continue until the magazine is empty. However, the trigger must be released between each burst.)