DEPARTMENT OF THE TREASURY
             BUREAU OF ALCOHOL, TOBACCO AND FIREARMS
                      WASHINGTON, DC 20226

                         NOV 5 1997                    F:SD:FTB:RLB
                                                       3311


Dear :

This is in response to your letter of October 23, 1997, to the
Bureau of Alcohol, Tobacco and Firearms. In your letter, you ask if
removing the steel receiver block from the lower receiver unit of
a Colt, Sporter rifle would be a violation of Federal law.

The steel receiver block to which you refer, is intended to serve
as an anti-tampering device and prevents the installation of
various AR-15 drop-in auto sears, lightning links, and M16
machinegun fire control components. The steel receiver block is
installed in the sporter lower receiver unit by Colt Firearms and
is an attempt, on Colt's part, to prevent the illegal conversion of
their semiautomatic sporter lower receivers units into machineguns
style receivers.  The presence of the steel receiver block is not
required by Federal law.

Based on our research, it is our opinion that the removal of the
steel receiver block, in and of itself, from the lower receiver
unit of a Colt, Sporter rifle would not result in a violation of
Federal law. In addition, the possession, sale, or transfer of a
Colt, Sporter lower receiver unit with the steel receiver block
removed would not constitute a violation at Federal law.

We trust that the foregoing has been responsive to your inquiry. If
we may be of any further assistance, please contact us.

                        Sincerely yours,


                      Edward M. Owen , Jr.
               Chief, Firearms Technology Branch