The following is the written response I received from the
B.A.T.F. regarding various methods of converting a G3 trigger pack to semi auto
only. The main question I had was if it would be legal to weld over or
weld a piece of round stock into the existing auto sear pin hole (with the auto
parts removed of course) which would eliminate the possibility of installing the
automatic fire control parts.
Department of the Treasury
Bureau of Alcohol, Tobacco, and Firearms
Washington, DC 20226
Sept 28, 2001
Mr. Jason Cotter
Mountain Home, AR 72653
Dear Mr. Cotter
This is in reply to your letter in which you have requested proper procedure
for modifying a Heckler and Koch G-3 machinegun trigger, into a semiautomatic
trigger.
To properly convert a G-3 machinegun trigger into a semiautomatic only
trigger there are several modifications needed. The modifications are
listed as follows:
1. Remove the automatic sear.
2. Grind off the automatic sear notch from the face of the hammer
3. Cut away the front corner of the trigger housing where the automatic
sear is mounted, .410-inch from the bottom and .540 inch from the front towards
the rear.
4. A new hole has to be drilled to accommodate the trigger
spring. The hole dimension is .200 inch drill that hole .165 inch from the
front of the new corner and .250 from the bottom of the new corner. These dimensions
are for the center of the hole.
5. The trigger spring should be replaced with a semiautomatic trigger
spring but the G-3 trigger spring will work.
6. The trigger over travel stop has to be moved towards the rear tang
of the trigger .150-inch
-2-
Mr. Jason Cotter
7. It will also be necessary to modify the trigger housing.
Modify the housing by cutting off the tabs for the front assembly pin.
Then adjust the fit of the housing into the receiver.
Title 26, United States code, Chapter 53, section 5845 (b), defines the term
machinegun as any weapon which shoots, is designed to shoot, or can be readily
restored to shoot, automatically more than one shot without manual reloading
with a single function of the trigger. The term shall also include the
frame or receiver of any such weapon, any part designed and intended solely and
exclusively, or combination of parts from which a machinegun can be assembled if
such parts are in possession or under control of a person.
If you do not properly modify the G-3 machinegun trigger pack and install it
in your semi automatic rifle, and that weapon fires more than one shot
automatically with a single function of the trigger, you would be in possession
of an unregistered machinegun.
We trust that the foregoing has been responsive to your inquiry. If we
can be of any further assistance, please contact us.
Sincerely yours,
Curtis Bartlett
Chief Firearms Technology Branch
