U.S. Department of Justice
Bureau of Alcohol, Tobacco
Firearms and Explosives
903050:RV
3311/2005-167
[url]www.atf.gov[/url]
Legal Department
Mr. Carlton S. Chen
Colt Defense LLC
547 New Park Avenue
West Hartford, CT 06110
Dear Mr. Chen:
This is in reference to your most recent facsimile transmitted to the Firearms Technology Branch (FTB), Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), on January 13, 2005. In your faxed letter, you seek clarification regarding the use of M16 machinegun bolt carriers in AR-15 type weapons.
As you are aware, since your provision of copies of relevant material in your previous faxes, ATF has previously addressed the use of M16 machinegun fire-control components in AR-15 type rifles in the General Information section of the Federal Firearms Regulations Reference Guide (ATF P 5300.4). (Please refer to page 115, item #3, “Important Information Concerning AR-15 Type Rifles.â€)
However, we would like to direct your attention to a particular paragraph of item #3, which states the following:
In order to avoid violations of the NFA, M16 hammers, triggers, disconnectors, selectors and bolt carriers must not be used in assembly of AR-15 type semiautomatic rifles, unless the M16 parts have been modified to AR-15 Model SP1 configuration. Any AR-15 type rifles which have been assembled with M16 internal components should have those parts removed and replaced with AR-15 Model SP1 type parts which are available commercially. The M16 components also may be modified to AR-15 Model SP1 configuration.
Accordingly, based on previous FTB recommendations not to install this bolt carrier and the conclusions presented in the passage cited above, our Branch cannot specifically authorize you to install an M16 bolt carrier into an AR15 rifle. Also, we cannot definitively tell you that installing an M16 bolt carrier in an AR 15 will make that firearm fire automatically.
We can only inform you that if this installation were to create a firearm that fires automatically, it would be a machinegun as defined; conversely, if it did not result in the production of a weapon that shoots automatically, it would be lawful to posses and make.
We thank you for your inquiry and trust the foregoing has been responsive.
Sincerely yours,
[signed]
Sterling Nixon
Chief, Firearms Technology Branch