List of Colt AR-15 variants

This article is a review of many variations of the Colt AR-15 family of weapons produced by Colt's Manufacturing Company. Weapons patterned on the original ArmaLite AR-15 have been produced by numerous manufacturers and have been used by nations around the world, some of which created their own variations. The tables here are split in a variety of categories, and provide an overview of different subtypes. For purposes of these tables, bold model numbers are weapons used (or previously used) by the U.S. Military while italic model numbers are weapons for commercial or export sale. See Glossary of terms for an explanation of each column.

Colt has been the most visible producer of weapons of the AR-15 pattern, and the military designation M16 is heavily associated with the company. Colt has an intricate internal nomenclature system for its models, with a variety of suffixes and prefixes. Colt’s systems have generally followed the times and though its model numbers originally came without prefixes, with the need to separate weapons made for civilian consumption from those made for military and law enforcement use, military models became prefixed with the code “RO.” For the purposes of this table, the RO nomenclature is obviated as this terminology did not exist in all cases, but it can be understood to be present. Military/LE models are also easily identified by their three digit code in contrast to the four digit codes for civilian weapons. Also, for the early Colt made ArmaLite AR-15 models, the charging handle was located within the carrying handle.

Colt’s civilian line is identified by a four digit code following a specific prefix. Initially all Colt civilian weapons were listed with an “R” prefix, with this changing to “AR” following the passage of the Federal Assault Weapons Ban in 1994. Colt also produced a line of weapons aimed at target shooters under the “MT” prefix, which stood for Match Target, as well as, the Colt Accurized Rifle, which was the only model to feature the CR prefix. Most recently with the shift in marketing policy by Colt Defense, these weapons have been given the “LE” and "LT" prefix. The "LT" series is modified version of the Colt 6720 featuring a lightweight "pencil" barrel with a free floating rail system. Only 1500 of the "LT" series were produced. Currently, Colt Defense has no line targeted specifically at the private civilian market.

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