Guys,

I want to know if anyone has attempted this on a colt preban BLUE label lower?  I dont know if it possible or legal?? I have seen where people have had them removed on these lowers but I have not even looked to see what holds it in place.  Is there anyone(gunsmith,machinist) that can do this...I do not intend to break the law by placing a DIAS or LL in the lower, I just dont like the half moon bolt and the sear block limits the bolt carriers that I can use...Someone give a brother some info??

I would suggest you sell the rifle to someone who does not care about that, and either buy an earlier Colt rifle or a another brand rifle without the block that you can have in the configuration you want.

Even after you remove it you will have an extra hole in your receiver, needing profesionally plugged,  have oversized trigger group pins and then that will start to eat at your craw.

It's possible and legal. I've removed the sear block from one of my preban Colts. I also did it in such a manner that a portion of the pin remained in the side of the lower receiver, so no ugly hole was left as a result. You should also be aware that you can use an uncut, full circle AR15 bolt carrier in conjunction with the sear block, so if that is your only concern, you really have no need to remove it. But I really had no need to remove mine, either. Just wanted to see if I could, I guess.

thanks for the input...I guess I will have to see what I can do.

FYI, on the sear blocked Colt 9mm AR15s, Colt cuts off the protruding part of the sear block that has "COLT" stamped on it.

I found this on http://www-2.cs.cmu.edu/afs/cs/user/wbardwel/public/nfalist/law.html

                  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  

[url=http://www.kurtskustomfirearms.citymax.com/page/page/8932.htm]Kurt[/url] removed the block from my lower receiver.  He did a hell of a job!