# List of Colt AR-15 and M16 rifle variants

This article describes the many variations of the Colt AR-15 and M16 rifle family of weapons produced by Colt's Manufacturing Company. Weapons patterned on the original ArmaLite AR-15 design 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 into 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 military models

Colt has been the most visible producer of ArmaLite AR-15 pattern weapons, and the military designations M16 and M4 are 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 "R0". For the purposes of this table, the R0 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.

### Colt Armalite AR-15

The original Armalite AR-15 models have the charging handle located on top of the upper receiver, protected within the carrying handle.
| Colt model no. | Name | Stock | Hand guards | Fire control | Rear sight | Forward assist | Case deflector | Caliber | Barrel length | Barrel profile | Barrel twist | Bayonet Lug | Muzzle device |
| 601 | ArmaLite AR-15 | A1 | Triangular | S-1-F | A1 | No | No | .223 REM | 20 in. | A1 | 1:14 (early) 1:12 (late) | Yes | Type 1 Duckbill Type 2 Duckbill |
| 602 | ArmaLite AR-15 (AKA: XM16) | A1 | Triangular | S-1-F | A1 | No | No | .223 REM | 20 in. | A1 | 1:12 | Yes | Type 2 Duckbill |

### Colt M16 Rifle, M4 Carbine based weapons

| Colt model no. | Name | Stock | Hand guards | Fire control | Rear sight | Forward assist | Case deflector | Caliber | Barrel length | Barrel profile | Barrel twist | Bayonet Lug | Muzzle device |
| 603 | XM16E1 | A1 | Triangular | S-1-F | A1 | Yes | No | .223 REM | 20 in. | A1 | 1:12 | Yes | Type 2 Duckbill or A1 Birdcage |
| 604 | M16 rifle | A1 | Triangular | S-1-F | A1 | No | No | .223 REM | 20 in. | A1 | 1:12 | Yes | A1 Birdcage |
| 605 | Model 605 | A1 | Triangular | S-1-F | A1 | No | No | .223 REM | 15 in. | A1 | 1:12 | No | Type 2 Duckbill |
| 605A | Model 605A | A1 | Triangular | S-1-F | A1 | Yes | No | .223 REM | 15 in. | A1 | 1:12 | No | Type 2 Duckbill |
| 605B | Model 605B | A1 | Triangular | S-F-1-3 | A1 | No | No | .223 REM | 15 in. | A1 | 1:12 | No | Type 2 Duckbill |
| 606 | CAR-15 Heavy Assault Rifle M1 | A1 | Triangular | S-1-F | A1 | No | No | .223 REM | 20 in. | HBAR | 1:12 | Yes | Type 2 Duckbill |
| 606A | CAR-15 Heavy Assault Rifle M1 | A1 | Triangular | S-1-F | A1 | Yes | No | .223 REM | 20 in. | HBAR | 1:12 | Yes | Type 2 Duckbill |
| 606B | CAR-15 Heavy Assault Rifle M1 | A1 | Triangular | S-F-1-3 | A1 | Yes | No | .223 REM | 20 in. | HBAR | 1:12 | Yes | Type 2 Duckbill |
| 607 | CAR-15 SMG | 1st Generation | Short Triangular | S-1-F | A1 | No | No | .223 REM | 10 in. | A1 | 1:12 | No | Type 1 and 2 Duckbill and 3.5" Moderator |
| 607A | CAR-15 SMG | 1st Generation | Short Triangular | S-1-F | A1 | Yes | No | .223 REM | 10 in. | A1 | 1:12 | No | Type 1 and 2 Duckbill and 3.5" Moderator |
| 607B | CAR-15 SMG | 1st Generation | Short Triangular | S-F-1-3 | A1 | No | No | .223 REM | 10 in. | A1 | 1:12 | No | Type 1 and 2 Duckbill and 3.5" Moderator |
| 608 | CAR-15 Survival Rifle | Tubular | Short Round | S-1-F | A1 | No | No | .223 REM | 10 in. | A1 | 1:12 | No | Conical or 3.5" Moderator |
| 609 | XM177E1 Commando | 2nd Generation | Short Ribbed | S-1-F | A1 | Yes | No | .223 REM | 10 in. | A1 | 1:12 | No | 3.5" or 4.5" Moderator |
| 610 | GAU 5/A | 2nd Generation | Short Ribbed | S-1-F | A1 | No | No | .223 REM | 10 in. | A1 | 1:12 | No | 3.5" or 4.5" Moderator |
| 610B | GAU 5/A | 2nd Generation | Short Ribbed | S-F-1-3 | A1 | No | No | .223 REM | 10 in. | A1 | 1:12 | No | 3.5" or 4.5" Moderator |
| 611 | M16 HBAR | A1 | Triangular | S-1-F | A1 | Yes | No | .223 REM | 20 in. | HBAR | 1:12 | Yes | A1 Birdcage |
| 611P | M16 HBAR (License produced by Elisco Tools) | A1 | Triangular | S-1-F | A1 | Yes | No | .223 REM | 20 in. | HBAR | 1:12 | Yes | A1 Birdcage |
| 613K | M16 (Licensed produced by Daewoo Precision Industries) | A1 | Triangular | S-1-F | A1 | Yes | No | .223 REM | 20 in. | A1 | 1:12 | Yes | A1 Birdcage |
| 613P | M16 (License produced by Elisco Tools) | A1 | Triangular | S-1-F | A1 | Yes | No | .223 REM | 20 in. | A1 | 1:12 | Yes | A1 Birdcage |
| 614 | M16A1 | A1 | Triangular | S-1-F | A1 | No | No | .223 REM | 20 in. | A1 | 1:12 | Yes | A1 Birdcage |
| 614S | M16S1 (Licence-produced by Chartered Industries of Singapore) | A1 | Triangular | S-1-F | A1 | No | No | .223 REM | 20 in. | A1 | 1:12 | Yes | A1 Birdcage |
| 615 | M16 HBAR | A1 | Triangular | S-1-F | A1 | No | No | .223 REM | 20 in. | HBAR | 1:12 | Yes | A1 Birdcage |
| 616 | M16 HBAR | A1 | Round | S-1-F | A1 | No | No | .223 REM | 20 in. | HBAR | 1:12 | Yes | A1 Birdcage |
| 619 | XM177 Commando | 2nd Generation | Short Ribbed | S-1-F | A1 | Yes | No | .223 REM | 10 in. | A1 | 1:12 | No | 3.5" or 4.5" Moderator |
| 620 | XM177 Commando | 2nd Generation | Short Ribbed | S-1-F | A1 | No | No | .223 REM | 10 in. | A1 | 1:12 | No | 3.5" or 4.5" Moderator |
| 621 | M16A1 HBAR | A1 | Triangular | S-1-F | A1 | Yes | No | .223 REM | 20 in. | HBAR | 1:12 | Yes | A1 Birdcage |
| 629 | Colt XM177E2 | 2nd Generation | Short Ribbed | S-1-F | A1 | Yes | No | .223 REM or 5.56 NATO | 11.5 in. | A1 | 1:12 | No | 4.5" Moderator |
| 630 | GAU 5/A | 2nd Generation | Short Ribbed | S-1-F | A1 | No | No | .223 REM | 11.5 in. | A1 | 1:12 | No | 4.5" Moderator |
| 633 | Colt SMG | 2nd Generation | Short Round | S-1-F | A1 | No | Yes | 9mm NATO | 7 in. | A1 | 1:10 | No | None |
| 634 | Colt SMG | 2nd Generation | Short Ribbed | Conflict between S-1 and S-1-F | A1 | No | Yes | 9mm NATO | 10 in. | A1 | 1:10 | No | A1 Birdcage |
| 635 | Colt SMG | 2nd, 3rd, or 4th Generation | Short Ribbed | S-1-F | A1 | No | Yes | 9mm NATO | 10 in. | A1 | 1:10 | No | A1 Birdcage |
| 635SD | Colt SMG | 2nd Generation | Short Ribbed | S-1-F | A1 | No | Yes | 9mm NATO | 10 in. | A1 w/ integral silencer | 1:10 | No | None |
| 639 | XM177 Commando | 2nd Generation | Short Ribbed | S-1-F | A1 | Yes | No | .223 REM | 11.5 in. | A1 | 1:12 | No | 4.5" Moderator or A1 |
| 639 | Colt SMG | 2nd | Short Ribbed | S-1-3 | A1 | No | Yes | 9mm NATO | 10 in. | A1 w/ integral silencer | 1:10 | No | A2 Compensator |
| 640 | XM177 Commando | 2nd Generation | Short Ribbed | S-1-F | A1 | No | No | .223 REM | 11.5 in. | A1 | 1:12 | No | 4.5" Moderator or A1 |
| 645 | M16A1E1 | A1 | Ribbed | S-1-3 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 Compensator |
| 645E | M16A2E1 | A2 | Ribbed | S-1-3 | Flattop (w/ flip down front sight) | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 Compensator |
| 646 | M16A2E3 | A2 | Ribbed | S-1-F | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 Compensator |
| 649 | GAU 5/A | 2nd Generation | Short Ribbed | S-1-F | A1 | No | No | .223 REM | 11.5 in. | A1 | 1:12 | No | 4.5" Moderator |
| 650 | M16A1 carbine/CAR15 | A1 | Short Ribbed | S-1-F | A1 | Yes | No | .223 REM | 14.5 in. | A1 | 1:12 | Yes | A1 Birdcage |
| 651 | M16A1 carbine/CAR15 | A1 | Short Ribbed | S-1-F | A1 | Yes | No | .223 REM | 14.5 in. | A1 | 1:12 | Yes | A1 Birdcage |
| 652 | M16A1 carbine/CAR15 | A1 | Short Ribbed | S-1-F | A1 | No | No | .223 REM | 14.5 in. | A1 | 1:12 | Yes | A1 Birdcage |
| 653 | M16A1 carbine/CAR15 | 2nd Generation | Short Ribbed | S-1-F | A1 | Yes | No | .223 REM | 14.5 in. | A1 | 1:12 | Yes | A1 Birdcage |
| 653P | M16A1 carbine/CAR15 (License produced by Elisco Tools) | 2nd Generation | Short Ribbed | S-1-F | A1 | Yes | No | .223 REM | 14.5 in. | A1 | 1:12 | Yes | A1 Birdcage |
| 654 | M16A1 carbine/CAR15 | 2nd Generation | Short Ribbed | S-1-F | A1 | No | No | .223 REM | 14.5 in. | A1 | 1:12 | Yes | A1 Birdcage |
| 655 | M16A1 Special High Profile | A1 | Triangular | S-1-F | A1 (used with special raised carry handle scope mount) | Yes | No | .223 REM | 20 in. | HBAR | 1:12 | Yes | A1 |
| 656 | M16A1 Special Low Profile | A1 | Triangular | S-1-F | Flattop | Yes | No | .223 REM | 20 in. | HBAR | 1:12 | Yes | A1 Birdcage |
| 701 | M16A2 | A2 | Ribbed | S-1-F | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 Compensator |
| 702 | M16A2 | A2 | Ribbed | S-1-3 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 Compensator |
| 703 | M16A2 Prototype | A2 | Ribbed | S-1-F | A2 | Yes | Yes | 5.56 NATO | 20 in. | A1 | 1:7 | Yes | A2 Compensator |
| 705 | M16A2 | A2 | Ribbed | S-1-3 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 Compensator |
| 707 | M16A2 | A2 | Ribbed | S-1-3 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A1 | 1:7 | Yes | A2 Compensator |
| 708 | M16A2 Enhanced | A2 | Ribbed | S-1-3-F | A2 | Yes | Yes | 5.56 NATO | 20 in. | A1 | 1:7 | Yes | A2 Compensator |
| 711 | M16A2 | A2 | Ribbed | S-1-F | A1 | Yes | No and Yes | 5.56 NATO | 20 in. | A1 | 1:7 | Yes | A2 Compensator |
| 713 | M16A2 | A2 | Ribbed | S-1-3 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 Compensator |
| 715 | M16A2 (License produced by Diemaco/Colt Canada as the C7) | A2 | Ribbed | S-1-F | A1 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 Compensator |
| 719 | M16A2 | A2 | Ribbed | S-1-3 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A1 | 1:7 | Yes | A2 Compensator |
| 720 | XM4 Carbine | 2nd Generation or 3rd Generation | Short Ribbed | S-1-F, S-1-3 | A1 or A2 | Earlier No, Later Yes | Earlier No, Later Yes | 5.56 NATO | 14.5 in. | A1 (Before), M4 (Current) | 1:7 | Yes | A1 or A2 Compensator |
| 723 | CAR-15 Delta Carbine | 3rd Generation | Short Ribbed | S-1-F | A1 | Earlier No, Later Yes | Earlier No, Later Yes | 5.56 NATO | 14.5 in. | Earlier A1, Later M4 | 1:7 | Yes | A2 Compensator |
| 725 | M16A2 carbine (License produced by Diemaco/Colt Canada as the C8) | 3rd Generation | Short Ribbed | S-1-F | A1 | Yes | Yes | 5.56 NATO | 14.5 in. | A1 | 1:7 | Yes | A2 Compensator |
| 725A | M16A2 carbine | 3rd Generation | Short Ribbed | S-1-F | A1 | Yes | Yes | 5.56 NATO | 14.5 in. | A1 | 1:7 | Yes | A2 Compensator |
| 725B | M16A2 carbine | 3rd Generation | Short Ribbed | S-1-F | A1 | Yes | Yes | 5.56 NATO | 14.5 in. | A2 | 1:7 | Yes | A2 Compensator |
| 726 | M16A2 carbine | 3rd Generation | Short Ribbed | S-1-F | A1 | Yes | Yes | 5.56 NATO | 14.5 in. | A1 | 1:7 | Yes | A1 Birdcage |
| 727 | M16A2 Government Carbine | 3rd Generation | Short Ribbed | S-1-F | A2 | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 Compensator |
| 728 | M16A2 carbine | 3rd Generation | Short Ribbed | S-1-F | A2 | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 Compensator |
| 733 | M16A2 Commando | 3rd or 4th Generation | Short Ribbed | S-1-F | A1 or A2 | Yes | Yes or No | 5.56 NATO | 11.5 in. | A1 or A2 | 1:7 | No | A1 or A2 |
| 733A | M16A2 Commando | 3rd or 4th Generation | Short Ribbed | S-1-3 | A1 or A2 | Yes | Yes or No | 5.56 NATO | 11.5 in. | A1 or A2 | 1:7 | No | A1 or A2 |
| 734 | M16A2 Commando | 3rd Generation | Short Ribbed | S-1-F | A1 or A2 | Yes | Yes or No | 5.56 NATO | 11.5 in. | A1 or A2 | 1:7 | No | A1 or A2 |
| 734A | M16A2 Commando | 3rd Generation | Short Ribbed | S-1-3 | A1 or A2 | Yes | Yes or No | 5.56 NATO | 11.5 in. | A1 or A2 | 1:7 | No | A1 or A2 |
| 735 | M16A2 Commando | 3rd or 4th Generation | Short Ribbed | S-1-3 | A1 or A2 | Yes | Yes or No | 5.56 NATO | 11.5 in. | A1 or A2 | 1:7 | No | A1 or A2 |
| 737 | M16A2 | A2 | Ribbed | S-1-3 | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| 738 | M16A2 Commando Enhanced | 3rd or 4th Generation | Short Ribbed | S-1-3-F | A2 | Yes | Yes | 5.56 NATO | 11.5 in. | A2 | 1:7 | No | A1 or A2 |
| 741 | M16A2 | A2 | Ribbed | S-1-F | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| 742 | M16A2 (Standard w/ bipod) | A2 | Ribbed | S-1-F | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| 745 | M16A2 (Standard w/ bipod) | A2 | Ribbed | S-1-3 | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| 746 | M16A2 (Standard w/ bipod) | A2 | Ribbed | S-1-3 | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| 750 | Colt Automatic Rifle (Colt/Diemaco project) | A2 | Square LMG | S-F | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| 777 | M4E1 Carbine | 4th Generation | M4 | S-1-F | A2 | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| 778 | M4 Carbine Enhanced | 4th Generation | M4 | S-1-3-F | A2 | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| 779 | M4 Carbine | 4th Generation | M4 | S-1-3 | A2 | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| 901 | M16A3 | A2 | Ribbed, Rail/RIS | S-1-F | Flattop | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| 905 | M16A4 | A2 | Ribbed, Rail/RIS | S-1-3 | Flattop | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| 920 | M4 Carbine | 4th Generation | M4, Rail/RIS | S-1-3 | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| 921 | M4A1 | 4th Generation | M4, Rail/RIS | S-1-F | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| 921HB | M4A1 | 4th Generation | M4, Rail/RIS | S-1-F | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 HBAR | 1:7 | Yes | A2 |
| 925 | M4E2 | 3rd or 4th Generation | M4, Rail/RIS | S-1-F (Earlier), S-1-3 (Later) | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| 927 | M4 Government Carbine | 4th Generation | M4, Rail/RIS | S-1-F | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| 933 | M4 Commando | 4th Generation | M4, Rail/RIS | S-1-F | Flattop | Yes | Yes | 5.56 NATO | 11.5 in. | A1 or A2 | 1:7 | No | A2 |
| 935 | M4 Commando | 4th Generation | M4, Rail/RIS | S-1-3 | Flattop | Yes | Yes | 5.56 NATO | 11.5 in. | A1 or A2 | 1:7 | No | A2 |
| 938 | M4 Commando Enhanced | 4th Generation | M4, Rail/RIS | S-1-3-F | Flattop | Yes | Yes | 5.56 NATO | 11.5 in. | A2 | 1:7 | No | A2 |
| 941 | M16A3 | A2 | Ribbed, Rail/RIS | S-1-F | Flattop | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| 942 | M16A3 (Standard w/ bipod) | A2 | Ribbed, Rail/RIS | S-1-F | Flattop | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| 945 | M16A4 | A2 | Ribbed, Rail/RIS | S-1-3 | Flattop | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| 950 | Colt Automatic Rifle (Colt/Diemaco project) | A2 | Square LMG | S-F | Flattop | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| 977 | M4A1 | 4th Generation | M4, Rail/RIS | S-1-F | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| 977HB | M4A1 | 4th Generation | M4, Rail/RIS | S-1-F | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 HBAR | 1:7 | Yes | A2 |
| 978 | M4 Carbine Enhanced | 4th Generation | M4, Rail/RIS | S-1-3-F | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| 979 | M4 Carbine | 4th Generation | M4, Rail/RIS | S-1-3 | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| 991 | Colt SMG | 4th Generation | M4, Rail/RIS | S-1-F | Flattop | No | Yes | 9mm NATO | 10.5 in. | A1 | 1:10 | No | A1 Birdcage |
| 992 | Colt SMG | 4th Generation | M4, Rail/RIS | S-1-3 | Flattop | No | Yes | 9mm NATO | 10.5 in. | A1 | 1:10 | No | A1 Birdcage |
| Colt model no. | Name | Stock | Hand guards | Fire control | Rear sight | Forward assist | Case deflector | Caliber | Barrel length | Barrel profile | Barrel twist | Bayonet Lug | Muzzle device |

### Colt military models without model numbers

In rare instances some Colt models have been produced without in house model numbers, or at least one which is readily apparent.
| Name | Stock | Hand guards | Fire control | Rear sight | Forward assist | Case deflector | Caliber | Barrel length | Barrel profile | Barrel twist | Bayonet Lug | Muzzle device |
| M16 PIP | A2 | Ribbed | S-1-F, S-1-3 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A1 or A2 |
| Colt Advanced Combat Rifle | Retractable ACR | ACR Type | S-1-3 or S-1-F | Flattop | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | No | ACR compensator |
| M231 FPW | FPW Wire | Short Round | S-F | None | No | No | .223 REM | 15.6 in. | HBAR | 1:12 | No | A1 |
| M231 Recoil Operated Rifle | None | Short Round | S-F | None | No | No | .233 REM | 15.6 in. | HBAR | 1:12 | No | A1 |
| Colt Advanced Piston Carbine | 4th Generation Retractable | Monolithic | S-1-F | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | Fluted | 1:7 | Yes | A2 |

### Diemaco/Colt Canada models

The Canadian company Colt Canada (formerly Diemaco) licensed production of a rifle (Colt Model 715) and carbine (Colt Model 725), but later went on to produce an entire line of AR-15/M16 pattern weapons developed independently. In May 2005, Colt's Manufacturing Company acquired Diemaco, and the name was changed to Colt Canada.
| Colt model no. | Diemaco model | Stock | Hand guards | Fire control | Rear sight | Forward assist | Case deflector | Caliber | Barrel length | Barrel profile | Barrel twist | Bayonet Lug | Muzzle device |
| 715 | C7 | A2 | Ribbed | S-1-F | A1 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| N/A | C7A1 | A2 | Ribbed | S-1-F | Weaver | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| N/A | C7A2 | Canadian 3rd Generation | Ribbed | S-1-F | Weaver | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| 750 | Colt/Diemaco LMG/LSW | A2 | Square LMG | S-F | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | No | A2 |
| N/A | LSW | A2 | Square LMG | S-F | Weaver | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | No | A2 |
| 725 | C8 | 3rd Generation | Short Ribbed | S-1-F | A1 | Yes | Yes | 5.56 NATO | 14.5 in. | A1 | 1:7 | Yes | A2 |
| N/A | C8A1 | Canadian 3rd Generation | Short Ribbed | S-1-F | Weaver | Yes | Yes | 5.56 NATO | 14.5 in. | A1 | 1:7 | Yes | A2 |
| N/A | C8FTHB | Canadian 3rd Generation | Short Ribbed | S-1-F | Weaver | Yes | Yes | 5.56 NATO | 14.5 in. | A2 | 1:7 | Yes | A2 |
| N/A | SFW | Canadian 3rd Generation | Short Ribbed | S-1-F | Weaver | Yes | Yes | 5.56 NATO | 16 in. | SFW | 1:7 | Yes | A2 |
| N/A | C8CQB | Canadian 3rd Generation | Short Ribbed | S-1-F | Weaver | Yes | Yes | 5.56 NATO | 10 in. | A2 | 1:7 | Yes | A2 |
| N/A | PDW | Canadian 3rd Generation | N/A | S-1-F | Weaver | Yes | Yes | 5.56 NATO | 5.7" in. | A2 | 1:7 | No | A2 |

### Non-factory military models

| Name | Base weapon | Stock | Hand guards | Fire control | Rear sight | Forward assist | Case deflector | Caliber | Barrel length | Barrel profile | Barrel twist | Bayonet Lug | Muzzle device |
| GUU-5/P | GAU-5/A or GAU-5A/A | 2nd or 3rd Generation | Short Ribbed | S-1-F | A1 | Yes | No | 5.56 NATO | 14.5 in. | A1 or M4 | 1:7 | Yes | A1 or A2 |
| GUU-5/P | GAU-5/A or GAU-5A/A | 2nd or 3rd Generation | M4 | S-1-F | A2 or Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| Mekut'zar | Model 653 | 3rd Generation or Israeli | Short Ribbed | S-1-F | A1 | Yes | No | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| Mekut'zrar | Model 653 | 2nd Generation or Israeli | Short Ribbed | S-1-F | A1 | Yes | No | 5.56 NATO | Variable; 9" average | A1 | 1:12 | No | Various |

## Colt civilian models

Colt's civilian line of semi-automatic Colt AR-15 rifles 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.

### R series models

| Colt model no. | Name | Stock | Hand guards | Fire control | Rear sight | Forward assist | Case deflector | Caliber | Barrel length | Barrel profile | Barrel twist | Bayonet Lug | Muzzle device |
| R6000 | AR-15 Sporter (SP1) | A1 | Triangular | S-1 | A1 | No | No | .223 REM | 20 in. | A1 | 1:12 | Yes | Type 2 Duckbill or A1 |
| R6001 | AR-15 Sporter Carbine (SP1 Carbine) | 2nd Generation | Short Ribbed | S-1 | A1 | No | No | .223 REM | 16 in. | A1 | 1:12 | Yes | A1 |
| R6002 | AR-15 Sporter (SP1; Bundled with 3× scope) | A1 | Triangular | S-1 | A1 | No | No | .223 REM | 20 in. | A1 | 1:12 | Yes | A1 |
| R6003 | AR-15 Sporter Carbine (SP1 Carbine; Bundled with 3× scope) | 2nd Generation | Short Ribbed | S-1 | A1 | No | No | .223 REM | 16 in. | A1 | 1:12 | Yes | A1 |
| R6004 | AR-15 Sporter (SP1; Bundled with Colt Reflex Sighting System) | A1 | Triangular | S-1 | A1 | No | No | .223 REM | 20 in. | A1 | 1:12 | Yes | A1 |
| R6007 | AR-15 Sporter (SP1 Coltguard electroless nickel) | A1 | Triangular | S-1 | A1 | No | No | .223 REM | 20 in. | A1 | 1:12 | Yes | A1 |
| R6010 | AR-15 Sporter (SP1) | A1 | Triangular | S-1 | A1 | No | No | .222 REM | 20 in. | A1 | 1:12 | Yes | A1 |
| R6420 | AR-15A2 Sporter II Carbine | 3rd Generation | Short Ribbed | S-1 | A1 | Yes | No & Yes | 5.56 NATO | 16 in. | A1 | 1:7 | Yes | A2 |
| R6430 | Sporter Lightweight (9 mm) | A2 | Short Ribbed | S-1 | A1 | No | Removable | 9mm NATO | 16 in. | A1 | 1:10 | Yes | A1 |
| R6450 | AR-15 9 mm Carbine | 3rd Generation | Short Ribbed | S-1 | A1 | No | No & Removable | 9mm NATO | 16 in. | A1 | 1:10 | Yes | A1 |
| R6500 | AR-15A2 Sporter II | A2 | Ribbed | S-1 | A1 | Yes | No & Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| R6510 | AR-15A2 Sporter II (Special export model in .222 Remington) | A2 | Ribbed | S-1 | A2 | Yes | No | .222 REM | 20 in. | A2 | 1:14 | Yes | A2 |
| R6520 | AR-15A2 Government Carbine | 3rd Generation | Short Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 16 in. | A1 | 1:7 | Yes | A2 |
| R6521 | Colt Carbine (AR-15A2 Government Carbine) (Special export model with receiver block and large pin upper receiver) | 3rd Generation | Short Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 16 in. | A1 | 1:7 | Yes/No | A2 |
| R6530 | Sporter Lightweight .223 | 3rd Generation | Short Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 16 in. | A1 | 1:7 | No | A2 |
| R6550 | AR-15A2 Government | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| R6550CC | AR-15A2 Government (w/ factory camouflage finish) | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| R6550K | AR-15A2 Government (w/ factory installed .22 Long Rifle conversion kit) | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| R6551 | Sporter Target | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| R6600 | AR-15A2 HBAR | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| R6600DH | AR-15A2 Delta HBAR (bundled w/ Tasco 3–9x scope and cheekpiece) | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| R6600K | AR-15A2 HBAR (w/ factory installed .22 Long Rifle conversion kit) | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | No | A2 |
| R6601 | Sporter Match HBAR | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | No | A2 |
| R6601DH | Sporter Match Delta HBAR (bundled w/ Tasco 3–9x scope and cheekpiece) | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | No | A2 |
| R6700 | Sporter Competition HBAR | A2 | Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 20 in. | HBAR | 1:9 | No | A2 |
| R6700CH | Sporter Competition HBAR (bundled w/ Tasco 3–9x scope and cheekpiece) | A2 | Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 20 in. | HBAR | 1:9 | No | A2 |
| R6700S | Sporter Competition HBAR (bundled w/ Tasco 3–9x scope) | A2 | Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 20 in. | HBAR | 1:9 | No | A2 |
| R6701 | Sporter Competition HBAR (Special limited edition production run) | A2 | Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 20 in. | HBAR | 1:9 | No | A2 |
| R6721 | AR-15A3 Tactical Carbine | 4th Generation | Short Ribbed | S-1 | A2 | Yes | Yes | .223 REM 5.56 NATO | 16 in. | HBAR | 1:9 | Yes | A2 |
| R6724 | Sporter Competition HBAR | A2 | Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 24 in. | HBAR | 1:9 | No | A2 |
| R6731 | AR-15A3 Competition HBAR | A2 | Short Ribbed | S-1 | A2 | Yes | Yes | .223 REM 5.56 NATO | 16 in. | HBAR | 1:9 | No | A2 |
| R6750 | Sporter Competition HBAR (bundled w/ bipod) | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | Super-Heavy | 1:7 | No | A2 |
| R6821 | Sporter Carbine (7.62×39mm) | 3rd Generation | Short Ribbed | S-1 | A2 | Yes | Yes | 7.62×39mm | 16 in. | HBAR | 1:12 | No | A1 |
| R6830 | Sporter Lightweight (7.62×39mm) | A2 | Short Ribbed | S-1 | A2 | Yes | Yes | 7.62×39mm | 16 in. | HBAR | 1:12 | No | A1 |

### AR series models

| Colt model no. | Name | Stock | Hand guards | Fire control | Rear sight | Forward assist | Case deflector | Caliber | Barrel length | Barrel profile | Barrel twist | Bayonet Lug | Muzzle device |
| AR6320 | AR-15 Lightweight | 4th Generation | Short Ribbed | S-1 | A1 | Yes | Yes | .223 REM 5.56 NATO | 16 in. | A1 | 1:9 | Yes | A2 |
| AR6450 | AR-15 9 mm Carbine | 3rd Generation | Short Ribbed | S-1 | A1 | No | Removable | 9mm NATO | 16 in. | A1 | 1:10 | Yes | A1 |
| AR6520 | AR-15A2 Government Carbine | 4th Generation | Short Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 16 in. | A1 | 1:7 | Yes | A2 |
| AR6520SP | AR-15A2 Government Carbine | 4th Generation | Short Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 10 in. | A2 | 1:7 | Yes | A2 |
| AR6525 | AR-15A2 Government Carbine | 4th Generation | Short Ribbed | S-1 | A2 | Yes | Yes | .223 REM 5.56 NATO | 16 in. | A2 | 1:9 | Yes | A2 |
| AR6530 | AR-15 Lightweight | A2 | Short Ribbed | S-1 | A2 | Yes | Yes | .223 REM 5.56 NATO | 16 in. | A1 | 1:7 | Yes | A2 |
| AR6551 | AR-15 Target Model | A2 | Ribbed | S-1 | A2 | Yes | Yes | .223 REM 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| AR6601 | AR-15 Match HBAR | A2 | Ribbed | S-1 | A2 | Yes | Yes | .223 REM 5.56 NATO | 20 in. | HBAR | 1:7 | Yes | A2 |
| AR6700 | AR-15 Competition HBAR | A2 | Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 20 in. | HBAR | 1:9 | Yes | A2 |
| AR15A4 | AR-15A4 Rifle | A2 | Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 20 in. | A2 | 1:7 | Yes | A2 |
| AR6720 | AR-15A4 Lightweight LE Carbine | 4th Generation | Short Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 16 in. | A1 | 1:7 | Yes | A2 |
| AR6721 | AR-15A3 Tactical Carbine | 4th Generation | Short Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 16 in. | HBAR | 1:9 | Yes | A2 |
| AR6721SP | AR-15A3 Tactical Carbine | 4th Generation | Short Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 10 in. | HBAR | 1:9 | Yes | A2 |
| AR6951 | Colt 9 mm Carbine | 4th Generation | Short Ribbed | S-1 | Flattop | No | Yes | 9mm NATO | 16.1 in. | A2 | 1:10 | Yes | A1 Birdcage |

### MT and CR series models

| Colt model no. | Name | Stock | Hand guards | Fire control | Rear sight | Forward assist | Case deflector | Caliber | Barrel length | Barrel profile | Barrel twist | Bayonet Lug | Muzzle device |
| CR6724 | Colt Accurized Rifle | A2 | FF Tube | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 24 in. | Stainless HBAR | 1:9 | No | None |
| CR6720 | Colt Accurized Rifle | A2 | FF Tube | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 20 in. | Stainless HBAR | 1:9 | No | None |
| CRM16A1 | M16A1 Retro Reissue | A1 | Triangular | S-1 | A1 | Yes | No | 5.56 NATO | 20 in. | A1 | 1:12 | Yes | Type 2 Duckbill |
| MT6400 | Match Target M4 | 4th Generation | M4 | S-1 | Flattop | Yes | Yes | 5.56 NATO | 16 in. | M4 | 1:7 | No | None |
| MT6400C | Match Target M4 | 4th Generation | M4 | S-1 | Flattop | Yes | Yes | 5.56 NATO | 16 in. | M4 | 1:7 | No | Factory compensator |
| MT6430 | Match Target Lightweight | A2 | Short Ribbed | S-1 | A1 | No | Yes | 9mm Luger | 16 in. | A1 | 1:10 | No | None |
| MT6530 | Match Target Lightweight | A2 | Short Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 16 in. | A1 | 1:7 | No | None |
| MT6551 | Match Target Rifle | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | A2 | 1:7 | No | None |
| MT6601 | Match Target HBAR | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | No | None |
| MT6601C | Match Target HBAR | A2 | Ribbed | S-1 | A2 | Yes | Yes | 5.56 NATO | 20 in. | HBAR | 1:7 | No | Factory compensator |
| MT6700 | Match Target Competition HBAR | A2 | Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 20 in. | HBAR | 1:9 | No | None |
| MT6700C | Match Target Competition HBAR | A2 | Ribbed | S-1 | Flattop | Yes | No | .223 REM 5.56 NATO | 20 in. | HBAR | 1:9 | No | Factory compensator |
| MT6731 | Match Target Competition HBAR II | A2 | Short Ribbed | S-1 | Flattop | Yes | Yes | .223 REM 5.56 NATO | 16 in. | HBAR | 1:9 | No | None |
| MT6830 | AR-15A2 Government Carbine (Post-Ban LE Only) | 3rd Generation | Short Ribbed | S-1 | A2 | Yes | Yes | .223 REM | 16 in. | HBAR | 1:12 | Yes | A2 |

### LE series models

| Colt model no. | Name | Stock | Hand guards | Fire control | Rear sight | Forward assist | Case deflector | Caliber | Barrel length | Barrel profile | Barrel twist | Bayonet Lug | Muzzle device |
| LE1020 | Gas Piston Carbine | 4th Generation | Rail System | S-1 | Flattop | Yes | Yes | 5.56 NATO | 16 in. | M4 | 1:7 | Yes | A2 |
| LE1033 | Gas Piston Commando | 4th Generation | Rail System | S-1 | Flattop | Yes | Yes | 5.56 NATO | 11.5 in. | A2 | 1:7 | Yes | A2 |
| LE6920 | Law Enforcement Carbine (Also produced under license by Colt Canada) | 4th Generation | M4 | S-1 | Flattop | Yes | Yes | 5.56 NATO | 16 in. | M4 | 1:7 | Yes | A2 |
| LE6920 SOCOM | Law Enforcement Carbine (US military reproduction) | 4th Generation | Knights armament RAS | S-1 | Matech rear sight | Yes | Yes | 5.56 NATO | 14.5 in. | SOCOM | 1:7 | Yes | Extended A2 |
| LE6920HB | Law Enforcement Carbine | 4th Generation | M4 | S-1 | Flattop | Yes | Yes | 5.56 NATO | 16 in. | M4 HBAR | 1:7 | Yes | A2 |
| LE6921 | M4LE Carbine | 4th Generation | M4 | S-1 | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 | 1:7 | Yes | A2 |
| LE6921CQB | M4LE Carbine | 4th Generation | M4 | S-1 | Flattop | Yes | Yes | 5.56 NATO | 10.5 in. | M4 HBAR | 1:7 | Yes | A2 |
| LE6921HB | M4LE Carbine | 4th Generation | M4 | S-1 | Flattop | Yes | Yes | 5.56 NATO | 14.5 in. | M4 HBAR | 1:7 | Yes | A2 |
| LE6921SP | M4LE Carbine | 4th Generation | M4 | S-1 | Flattop | Yes | Yes | 5.56 NATO | 10 in. | M4 HBAR | 1:7 | Yes | A2 |
| LE6933 | M4LE Commando | 4th Generation | Short Ribbed | S-1 | Flattop | Yes | Yes | 5.56 NATO | 11.5 in. | A2 | 1:7 | Yes | A2 |
| LE6940 | Monolithic Advanced Law Enforcement Carbine | 4th Generation | Monolithic Rail System | S-1 | Flattop | Yes | Yes | 5.56 NATO | 16 in. | M4 | 1:7 | Yes | A2 |
| LE6941 | Law Enforcement Carbine (direct impingement version of LE1020) | 4th Generation | Rail System | S-1 | Flattop | Yes | Yes | 5.56 NATO | 16 in. | M4 | 1:7 | Yes | A2 |

### LT series models

| Colt model no. | Name | Stock | Hand guards | Fire control | Rear sight | Forward assist | Case deflector | Caliber | Barrel length | Barrel profile | Barrel twist | Bayonet Lug | Muzzle device |
| LT6720-R | Talo Special Edition | 4th Generation | Rail System | S-1 | Flattop | Yes | Yes | 5.56 NATO | 16 in. | Lightweight pencil barrel | 1:7 | No | A2 |

## Glossary of terms
### Stock

Fixed Stocks
* A1: Fixed stock as used on M16 and M16A1. May or may not have a trapdoor to store a cleaning kit
* A2: Improved stock used on M16A2. Longer by 5/8"
* Tubular: Fixed tubular buttstock, similar to the 2nd Generation retractable unit, using a receiver extension and triangular rear with buttplate
Retractable Stocks
* 1st Generation: 2-position sliding stock that resembled a shortened fixed buttstock
* 2nd Generation: 2-position aluminum retractable stock
* 3rd Generation: 2-position fiberlite retractable stock. Introduced 1985
* Canadian 3rd Generation: 4-position fiberlite retractable stock fitted with rubber buttpad
* 4th Generation: 4-position nylon retractable stock. Introduced 2002, designed by Picatinny Arsenal engineer Lily Ko with reinforced ribs, an angled buttplate, and a rear sling swivel
* Retractable ACR: Similar in design to the so-called "Crane Stock" (initially fabricated by the Naval Surface Warfare Center Crane Division) essentially a 3rd generation unit with integrated cheek-rest
* FPW Wire: Retractable wire stock similar in appearance to the stock used on the M3 submachine gun
* Israeli: Rebuilt 3rd Generation stocks with 6 positions instead of 2

### Handguards

* Triangular: Triangular rifle handguards
* Short Triangular: Carbine length triangular handguards
* Round: Smooth round rifle handguards
* Short Round: Carbine length smooth round handguard
* Ribbed: Ribbed round rifle handguards
* Short Ribbed: Carbine length ribbed handguards
* Square LMG: Special heavy handguards with integral vertical grip for use during sustained fire
* FF Tube: Free-Float Tube
* M4: Oval carbine handguards with double heatshields
* Rail/RIS: Handguards are replaced with a Rail Integration System.
* Monolithic Rail Platform (MRP): A variant Rail System made by LMT. It has a free-floating barrel for greater accuracy.
* ACR Type: Advanced Combat Rifle Project Handguard

### Fire control

* S-1: The selector is Safe (S) – Semi-Automatic (1)
* S-F: The selector is Safe (S) – Fully Automatic (F)
* S-1-F: The selector is Safe (S) – Semi-Automatic (1) – Fully Automatic (F)
* S-1–3: The selector is Safe (S) – Semi-Automatic (1) – 3-Round Burst (3)
* S-F-1–3: The selector is Safe (S) – Fully Automatic (F) – Semi-Automatic (1) – 3-Round Burst (3). First Generation 4 position group
* S-1–3-F: The selector is Safe (S) – Semi-Automatic (1) – 3-Round Burst (3) – Fully Automatic (F). Second Generation 4 position group

### Rear sight

* A1: "Field sights" in which the rear sight is only adjustable for windage
* A2: Rear sight adjustable for both windage and elevation
* Flattop: Indicates carry handle and rear sight has been replaced with a MIL-STD-1913 rail. A detachable carry handle can be attached to the rail which features either A1 (Diemaco/Colt Canada) or A2 (Colt) sights
* Weaver: Indicates carry handle and rear sight has been replaced with a Weaver-type rail. A detachable carry handle can be attached to the rail which features either A1 (Diemaco/Colt Canada) or A2 (Colt) sights

### Barrel profile

* ArmaLite Early ArmaLite AR-15 ultra-lightweight 'Hollywood' turned-down profile barrel, 1:14 twist only
* A1: Also referred to as the "lightweight" or "pencil" profile. Government-specified barrel profile increased to between 0.675 and 0.575 inches
* A2: Also referred to as the "government" or "gov't" profile. Barrel profile for which the portion of the barrel in front of handguards is thickened to 0.715 inches
* HBAR: A barrel that in some portion is thicker than government-profile, usually underneath the handguards
* M4: Government barrel profile with small portion reduced to 0.575 inches to mount M203 grenade launcher
* M4 HBAR: M4 barrel with portion under handguard thickened for sustained automatic fire
* Super Heavy: Special Colt bull target/match barrel
* SFW: Special Forces Weapon profile, A2 profile with "fat" portion forward of the sight triangle

### Barrel twist

Note: Metric measurements are rounded upwards to the nearest digit.
* 1:14: 1 right hand twist every 14 inches (356 mm) .222 Remington or .223 Remington (US M193)
* 1:12: 1 right hand twist every 12 inches (305 mm) .223 Remington (US M193) or 7.62×39mm
* 1:10: 1 right hand twist every 10 inches (254 mm) 9×19mm NATO
* 1:9: 1 right hand twist every 9 inches (229 mm) .223 Remington & 5.56×45mm NATO
* 1:7: 1 right hand twist every 7 inches (178 mm) 5.56×45mm NATO (NATO SS109 & US M855)

### Muzzle device

* Type 1 Duckbill: Original three-prong flash hider
* Type 2 Duckbill: Also referred to as "three prong." A larger three-prong flash hider
* A1 or A1 Birdcage: Also referred to as Birdcage flash hider
* A2 or A2 Compensator: Birdcage flash hider with bottom slots closed off to act as muzzle compensator and to prevent dust from being blown into the shooters face while in the prone position
* 3.5" Moderator or 4.5" Moderator: Either the 3.5-inch or 4.5-inch baffled moderators
* Conical: A conical flash suppressor
* ACR Compensator: Special anti-rise muzzle device developed specifically for the Colt ACR
* Factory Compensator: Colt Factory muzzle brake compliant with the restrictions of the 1994 Federal Assault Weapons Ban