- Technically speaking, Colt serial numbers tend jump all over the place with no set pattern. That’s why it’s difficult to understand them without a point of reference. Design changes can also change the look of the serial numbers. For example, there is the issue of the 1970s Colt M1911’s commercial production.
- CC (Colt Carbine) Colt Model 6520 AR-15A2 Government Model Carbine(1988-) This prefix was used I think on the first 1,600rifles only, before they switched to using GC (GovernmentCarbine).
1 - Colt built several thousand 'bastardized' AR-15's using different lower receivers but the same model number. Depending on the date of manufacture it may have an A1 or an A2 lower receiver. There doesn't seem to be a definitive list of which rifles have which receiver, or when Colt began using strictly A2 receivers for their AR-15's. The year/serial numbers under Colt SP series was forwarded to me by an individual whose return address I no longer have. Double asterisk (.) under Bushmaster, a person on the internet e-mailed me that he had a lower that was shipped stripped (thus not a complete rifle) in 1991 from Bushmaster with serial #0327XX – ALWAYS CALL TO VERIFY.
Colt Commercial Variants
| This table is a mirror of a work in progress by Andy Krywonizka at http://come.to/ar15/ - For the most recent version of the table please visit Andy's site. - Many thanks to Andy for allowing the reproduction of his work here. |
| This table is intended to be used as a reference for the Colt-series of automatic rifles based on the AR-15 pattern. Currently the R6xxx and some of the military 3-digit series are covered, but not all of the information is complete. If you know something about the rifles listed or find an error, please e-mail me and I'll update the table. The colums I'm specifically seeking info on have violet-colored headers. |
Click here for definitions of the terms used in this table.
| Model No. | Pull (in) | ||||||||||||||||||||
| R6000 | AR-15 Sporter (SP1) | .223 | 20 | Standard | 1:12' | 7.5 | No | Yes | No | A1 | A1 | Straight | 3-prong | 13 | Straight | Smooth triangular | Safe, semiautomatic | --- | 1964 | 1985 | |
| R6001 | AR-15 Sporter w/collapsible stock (SP1 Carbine) | .223 | 16 | Standard | 1:12' | 5.8 | No | Yes | No | A1 | A1 | Straight | Birdcage | --- | Straight | Ribbed shorty | Safe, semiautomatic | --- | 1977 | 1985 | |
| R6222 | AR-15 .22 LR Conversion Kit | .22 LR | --- | --- | --- | 1.2 | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | 1990 | --- | |
| R6420 | AR-15 Carbine | .223 | 16 | Standard | 1:7' | 5.8 | Yes | Yes | No | A1 | A2 | Tapered | Ribbed shorty | Safe, semiautomatic | --- | 1985 | 1987 | ||||
| R6430 | Sporter Lightweight | 9x19mm | 16 | Standard | 1:10' | 7.1 | No | Yes | No | A1 | A2 | Tapered | Ribbed shorty | Safe, semiautomatic | --- | 1992 | --- | Has special deflector | |||
| R6450 | AR-15 9mm Carbine | 9x19mm | 16 | Standard | 1:10' | 6.3 | No | Yes | No | A1 | A2 | Tapered | Ribbed shorty | Safe, semiautomatic | --- | 1985 | 1987 | ||||
| R6500 | AR-15A2 | .223 | 20 | A2 | 1:7' | 7.8 | Yes | Yes | No | A1 | A1 | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | 1984 | 1988 | Also made in 1989 only | ||
| R6510 | AR-15A2 | .222 | 20 | A2 | 1:7' (?) | 7.8 | Yes | Yes | No | A1 | A1 | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | Made for export to countries where .223 Rem was considered a military round | ||||
| R6520 | AR-15A2 Gov't Model Carbine | .223 | 16 | Standard | 1:7' | 5.8 | Yes | Yes | Yes | A1* | A2 | A2 | Tapered | Ribbed shorty | Safe, semiautomatic | --- | 1988 | 1990 | |||
| R6530 | Sporter Lightweight | .223 | 16 | Standard | 1:7' | 6.7 | Yes | No | Yes | A1* | A2 | A2 | Tapered | Ribbed shorty | Safe, semiautomatic | --- | 1991 | --- | |||
| R6550 | AR-15A2 Gov't Model | .223 | 20 | A2 | 1:7' | 7.5 | Yes | Yes | Yes | A2* | A2 | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | 1988 | 1990 | |||
| R6551 | Sporter Target | .223 | 20 | A2 | 1:7' | 7.5 | Yes | No | Yes | A2* | A2 | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | 1991 | --- | |||
| R6600 | AR-15A2 H-BAR | .223 | 20 | HBAR | 1:7' | 8.0 | Yes | Yes | Yes | A2* | A2 | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | 1986 | 1991 | |||
| R6600DH | AR-15A2 Delta H-BAR | .223 | 20 | HBAR | 1:7' | 10.0 | Yes | Yes | Yes | A2* | A2 | A2 | Tapered | Ribbed cylindrical | Safe, Semiautomatic | --- | 1987 | 1990 | 3-9X scope, cheekpiece | ||
| R6601 | Sporter Match HBAR | .223 | 20 | HBAR | 1:7' | 8.0 | Yes | No | Yes | A2* | A2 | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | 1991 | --- | |||
| R6601DH | Sporter Match Delta HBAR | .223 | 20 | HBAR | 1:7' | 10.0 | Yes | No | Yes | A2* | A2 | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | 1991 | 1992 | 3-9X scope, cheekpiece | ||
| R6700 | Sporter Competition HBAR | .223 | 20 | HBAR | 1:9' | 8.5 | Yes | No | Yes | A2 | A2 (detachable) | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | 1992 | --- | |||
| R6700CH | Sporter Competition HBAR (select) | .223 | 20 | HBAR | 1:9' | 10.5 | Yes | No | Yes | A2 | A2 (detachable) | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | 1992 | --- | 3-9X scope, cheekpiece | ||
| R6700DC | Sporter Conversion Kit | .223 | 20 | HBAR | 1:9' | 5.5 | Yes | No | Yes | --- | none | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | 1993 | --- | Flattop | ||
| R6830 | Sporter Lightweight | 7.62x39mm | 16 | HBAR | 1:12' | 7.5 | Yes | No | Yes | A2 | A2 | A2 | Tapered | Ribbed shorty | Safe, semiautomatic | --- | 1993 | --- | |||
| R6850DC | Sporter Conversion Kit | 7.62x39mm | 16 | HBAR | 1:12' | 4.2 | Yes | No | Yes | --- | none | A2 | Tapered | Ribbed shorty | Safe, semiautomatic | --- | 1993 | --- | Flattop | ||
| R6851DC | Sporter Conversion Kit | 7.62x39mm | 20 | HBAR | 1:12' | 5.4 | Yes | No | Yes | --- | none | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | 1993 | --- | Flattop | ||
| R6900DC | Sporter Conversion Kit | .223 | 20 | HBAR | 1:9' | 5.8 | Yes | No | Yes | --- | A2 | A2 | Tapered | Ribbed cylindrical | Safe, semiautomatic | --- | 1993 | --- | |||
| 633 | 9mm Submachine Gun | 9x19mm | 7 | Standard | 1:10' | 5.4 | No | No | Yes | A2 | A1 | Grooved | None | Tapered | Smooth cylindrical | Safe, semiautomatic, full automatic | 700-900 | Mechanical buffer, flip-down front sight | |||
| 633HB | 9mm Submachine Gun | 9x19mm | 7 | Standard | 1:10' | 5.4 | No | No | Yes | A2 | A1 | Grooved | None | Tapered | Smooth cylindrical | Safe, semiautomatic, full automatic | 700-900 | Hydraulic buffer, flip-down front sight | |||
| 634 | 9mm Submachine Gun | 9x19mm | 7 or 10.5 | Standard | 1:10' | 5.4 | No | No | Yes | A2 | A1 | Grooved | None | Tapered | Smooth cylindrical on 7' model, ribbed shorty on 10.5' model | Safe, semiautomatic | --- | Flip-down front sight on 7' model | |||
| 635 | 9mm Submachine Gun | 9x19mm | 7 or 10.5 | Standard | 1:10' | 5.4 | No | No | Yes | A2 | A1 | Grooved | None | Tapered | Smooth cylindrical on 7' model, ribbed shorty on 10.5' model | Safe, semiautomatic, full automatic | 700-900 on 7' model, 800-1000 on 10.5' model | Flip-down front sight on 7' model | |||
| 639 | 9mm Submachine Gun | 9x19mm | 7 or 10.5 | Standard | 1:10' | 5.4 | No | No | Yes | A2 | A1 | Grooved | None | Tapered | Smooth cylindrical on 7' model, ribbed shorty on 10.5' model | Safe, semiautomatic, 3-shot burst | 700-900 on 7' model, 800-1000 on 10.5' model | Flip-down front sight on 7' model | |||
| 701 | M16A2 Rifle | .223 | 20 | HBAR | 1:7' | 7.9 | Yes | Yes | Yes | A2 | A2 | Grooved | A2 | 13 5/8' | Tapered | Ribbed cylindrical | Safe, semiautomatic, full automatic | 700-950 | |||
| 705 | M16A2 Rifle | .223 | 20 | HBAR | 1:7' | 7.9 | Yes | Yes | Yes | A2 | A2 | Grooved | A2 | 13 5/8' | Tapered | Ribbed cylindrical | Safe, semiautomatic, 3-shot burst | 700-950 | Standard U.S. Military service rifle | ||
| 715 | M16A2 Rifle | .223 | 20 | HBAR | 1:7' | 7.9 | Yes | Yes | Yes | A2 | A1 | Grooved | A2 | 13 5/8' | Tapered | Ribbed cylindrical | Safe, semiautomatic, full automatic | 700-950 | |||
| 719 | M16A2 Rifle | .223 | 20 | HBAR | 1:7' | 7.9 | Yes | Yes | Yes | A2 | A1 | Grooved | A2 | 13 5/8' | Tapered | Ribbed cylindrical | Safe, semiautomatic, 3-shot burst | 700-950 | |||
| 720 | M16A2 (M4) Carbine | .223 | 14.5 | HBAR stepped | 1:7' | 5.7 | Yes | Yes | Yes | A2 | A1 or A2 | Grooved | A2 | Tapered | Ribbed shorty | Safe, semiautomatic, full automatic or 3-shot burst | 700-950 | ||||
| 727 | M16A2 Carbine | .223 | 14.5 | HBAR stepped | 1:7' | 5.7 | Yes | Yes | Yes | A2 | A2 | Grooved | A2 | Tapered | Ribbed shorty | Safe, semiautomatic, full automatic | 700-950 | ||||
| 733 | M16A2 Commando | .223 | 11.5 | HBAR | 1:7' | 5.4 | Yes | Yes | Yes | A2 | A2 | Grooved | A2 | Tapered | Ribbed shorty | Safe, semiautomatic, full automatic | 700-1000 | ||||
| 735 | M16A2 Commando | .223 | 11.5 | HBAR | 1:7' | 5.4 | Yes | Yes | Yes | A2 | A2 | Grooved | A2 | Tapered | Ribbed shorty | Safe, semiautomatic, 3-shot burst | 700-1000 | ||||
| 750 | M16A2 Light Machine Gun | .223 | 20 | MG HBAR | 1:7' | 12.8 | No | No | Yes | A2 | A2 | Grooved | A2 | 13 5/8' | Tapered | Square LMG | Safe, full automatic | 600-750 | Bipod, front grip, carry handle, fires from open bolt |
1 - Colt built several thousand 'bastardized'AR-15's using different lower receivers but the same model number. Dependingon the date of manufacture it may have an A1 or an A2 lower receiver.There doesn't seem to be a definitive list of which rifles have which receiver,or when Colt began using strictly A2 receivers for their AR-15's.
Colt M16 Rifle Models
Courtesy Janes Infantry Weapons 1997/98, and Small Armsof the World (1983) by Edward C. Ezell.| Model Name | Description | Roll Marked (left) | Roll Marked (right) | |
| 601 | AR-15 | AR-15 rifle | Colt Armalite AR15 Patents Pending Cal. .223 Model 01 Serial 0000000 | |
| 602 | AR-15 | AR-15 rifle. Early US Government purchase - no forwardassist. | Colt AR-15 Property of US Gov't Cal. .223 Model 02 Serial 0000000 | |
| 603 | M16A1 | M16A1 rifle. Originally the XM16E1. Standard US Governmentmodel with forward assist. | Property of US Gov't M16A1 Cal 5.56mm 0000000 | |
| 603K | M16A1 | M16A1 rifle. Produced for South Korea. | M16A1 K0000000 | Made in Korea Under License from Colt's, Hartford, CT. U.S.A. |
| 604 | M16 | M16 rifle. Produced for US Air Force without forwardassist. | Property of US Gov't M16 Cal 5.56mm 0000000 | |
| 605A | M16 carbine. Carbine version of M16A1 rifle with forwardassist and fixed buttstock. | |||
| 605B | M16 carbine. Same as Model 605A but with additional three-roundburst limiter; no forward assist. | |||
| 606 | HBAR | Heavy Barrel Assault Rifle (HBAR) without forward assist.Also known as the Heavy Assault Rifle M1. | Mod 606 Cal 5.56mm 0000000 | |
| 606A | Heavy Barrel Assault Rifle (HBAR) with forward assist. | |||
| 606B | Heavy Barrel Assault Rifle (HBAR) with forward assistand three-round burst limiter. | |||
| 607 | Submachine gun with sliding buttstock and 10' (254 mm)barrel. | |||
| 608 | CAR-15 survival rifle with 10' (254 mm) barrel and fixedtubular buttstock. About 10 produced. | |||
| 609 | SMG #1 XM177E1 Commando | XM177E1 submachine gun for US Army with 10' (254 mm)barrel and 3.5' (89 mm) long sound/flash suppressor. | Property of US Gov't Commando Cal 5.56mm 0000000 | |
| 610 | S.M.G. #2 XM177 | XM177E1 submachine gun for US Air Force with 10' (254mm) barrel. | Property of US Gov't SMG 5.56mm 0000000 | |
| 610B | XM177E1 submachine gun for US Air Force with additionof three-round burst limiter. | |||
| 611 | HBAR | Heavy Barrel Assault Rifle. Export model of Model 606. | Mod 611 Cal 5.56mm 0000000 | |
| 611P | HBAR | Heavy Barrel Assault Rifle. Export model of Model 611for the Philippines. | Made by Elisco Tool for the Republic of The Phillipines M16A1 RP0000000 | Made in the Phillipines Under License from Colt's, Hartford, CT. U.S.A. |
| 613 | AR-15 | M16A1 rifle. Export version of Model 603. | Mod 613 Cal 5.56mm 0000000 | |
| 613P | AR-15 | M16A1 rifle. Export version of Model 613 for the Philippines. | Made by Elisco Tool for the Republic of The Phillipines M16A1 RP0000000 | Made in the Phillipines Under License from Colt's, Hartford, CT. U.S.A. |
| 614 | AR-15 | M16 rifle. Export version of Model 604 without forwardassist. | Mod 614 Cal 5.56mm 0000000 | |
| 614S | AR-15 | M16 rifle. Export version of Model 614 license producedby Chartered Industries of Singapore. | C I S Made in Singapore by Chartered Industries of SingaporeLimited Under License from Colt Industries Hartford, Conn, USA Patented | |
| 616 | HBAR | Heavy Barrel Assault Rifle. Export version of Model 606. | Property of US Gov't Mod 616 Cal 5.56mm 0000000 | |
| 619 | S.M.G. | Submachine gun. Export version of Model 609. | Mod 619 Cal 5.56mm 0000000 | |
| 620 | S.M.G. | Submachine gun. Export version of Model 610. | Mod 620 Cal 5.56mm 0000000 | |
| 621 | HBAR | Heavy Barrel Assault Rifle. Heavy barrel version of Model603. | Property of US Gov't Mod 621 Cal 5.56mm 0000000 | |
| 629 | XM177E2 | XM177E2 submachine gun for US Army with 11.5' (292 mm)barrel and 4.5' (114 mm) long sound/flash suppressor. | Property of US Gov't XM177E2 Cal 5.56mm 0000000 | |
| 630 | Submachine gun for US Air Force without forward assistand 11.5' barrel. | |||
| 633 | 9 mm submachine gun with 7' (178 mm) barrel and mechanicalbuffer. | |||
| 633HB | 9 mm submachine gun with 7' (178 mm) barrel and hydraulicbuffer. | |||
| 634 | 9 mm submachine gun with 10.5' (267 mm) barrel, withoutforward assist. | |||
| 635 | 9 mm submachine gun with 10.5' (267 mm) barrel, withoutforward assist. | |||
| 639 | S.M.G. | Submachine gun. Export version of Model 629. | Mod 639 Cal 5.56mm 0000000 | |
| 640 | S.M.G. | Submachine gun. Export version of Model 629 without forwardassist. | Mod 640 Cal 5.56mm 0000000 | |
| 645 | M16A2 rifle. Standard US Government model with revised1 in 7' (1 in 177.8 mm) rifling, 20' (508 mm) barrel and new rear sight. | |||
| 645E | M16A2 rifle 'Enhanced'. Modified M16A2 with removablecarrying handle for optical sight mounting and flip-up front sight. | |||
| 649 | S.M.G. | Sumachine gun. For US Air Force, with 14' (356 mm) barreland 1 in 12' (1 in 305 mm) rifling. | Property of US Gov't GAU-5/A/A Cal 5.56mm 0000000 | |
| 651 | M16A1 carbine. Export model with 14.5' (368 mm) barreland full size stock. | |||
| 652 | M16A1 carbine. Export model with 14.5' (368 mm) barreland full size stock, but without forward assist. | |||
| 653 | M16A1 carbine. Export model with 14.5' (368 mm) barreland sliding stock. | |||
| 653P | M16A1 carbine. Export model with 14.5' (368 mm) barreland sliding stock, license produced in the Philippines. | Made by Elisco Tool for the Republic of the Phillipines M16A1 RP0000000 | MAde in the Phillipines Under License from Colt's, Hartford, CT. U.S.A. | |
| 654 | M16 carbine. Export model without forward assist. Fittedwith 14.5' (368 mm) barrel and sliding stock. | |||
| 655 | M16A1 sniper rifle. Experimental model with high profileupper receiver. | |||
| 656 | M16A1 sniper rifle. Experimental model with low profileupper receiver and Sionics suppressor. | |||
| 701 | M16A2 rifle. Export model with full automatic in placeof three-round burst limiter. | |||
| 702 | M16A2 rifle. Export model for United Arab Emirates withM16A1 rear sights and full automatic in place of three-round burst limiter. | |||
| 703 | M16A2 rifle. Export model for the United Arab Emirateswith M16A1 barrel profile and full automatic in place of three-round burstlimiter. | |||
| 705 | M16A2 rifle. Export model with full automatic in placeof three-round burst limiter. Also known as M16A2E3. | |||
| 707 | M16A2 rifle. Export model with three-shot burst limiterand M16A1 barrel profile. | |||
| 711 | M16A2 rifle. Export model with M16A1 rear sight and M16A1barrel profile. | |||
| 715 | M16A2 rifle. Canadian version of M16A2 rifle known asC7 with M16A1 rear sight and M16A2 barrel. License produced by Diemaco. | |||
| 719 | M16A2 rifle. Version of Model 715 produced by Colt withthree-round burst limiter. | |||
| 720 | M4 carbine. Originally known as M16A2 carbine, with 14.5'(370 mm) barrel. | |||
| 723 | M16A2 carbine. Produced for United Arab Emirates andUS Army Delta Force. With M16A1 rear sight, 14.5' (370 mm) barrel and fullautomatic fire capability. | |||
| 725 | M16A2 carbine. Canadian version of M16A2 carbine knownas C8 with M16A1 rear sight and M16A2 barrel. License produced by Diemaco. | |||
| 725A | M16A2 carbine. Export version of the M16A2 carbine producedby Colt for United Arab Emirates with M16A1 barrel profile. | |||
| 725B | M16A2 carbine. Export version of M16A2 carbine with M16A2barrel. | |||
| 727 | M16A2 carbine. Carbine with full automatic fire featureproduced for (among others) the US Navy. With 14.5' (370 mm) barrel. | |||
| 733 | M16A2 Commando. Short-barrelled model with full automaticfire, 11.5' (290 mm) barrel and M16A1 rear sight. | |||
| 733A | M16A2 Commando. Short-barrelled model with three-roundburst limiter in place of full automatic fire, 11.5' (290 mm) barrel andM16A1 rear sight. | |||
| 735 | M16A2 Commando. Similar to Model 733 but with three-roundburst limiter. | |||
| 737 | M16A2 Heavy Barrel Assault Rifle (HBAR). With M16A1 rearsight. | |||
| 741 | M16A2 Heavy Barrel Assault Rifle (HBAR). As Model 737but with M16A2 rear sight. | |||
| 750 | M16A2 Squad Automatic Weapon (SAW). With 20' (508 mm)barrel, bipod and front handguard assembly. Fully automatic. | |||
| 901 | M16A3 rifle. Similar to Model 701 but with flat top railunder carrying handle. Fully automatic. | |||
| 905 | M16A3 rifle. Similar to Model 705 but with flat top railunder carrying handle. Three-round burst limiter. | |||
| 925 | M16A3 rifle. Similar to Model 725 but with flat top railunder carrying handle. Three-round burst limiter. | |||
| 927 | M4A1 carbine. Originally known as M16A3 carbine. Similarto Model 727 but with flat top rail under carrying handle. Fully automatic.In production for Joint DoD Special Forces. | |||
| 941 | M16A3 Heavy Barrel Assault Rifle (HBAR). Similar to Model741 but with flat top rail under carrying handle. Semi and fully automatic. | |||
| 942 | M16A3 Squad Automatic Weapon (SAW). Similar to Model741 but with flat top rail under carrying handle. Fully automatic only. | |||
| 950 | M16A3 Squad Automatic Weapon (SAW). Similar to Model741 but with flat top rail under carrying handle. Fully automatic only. |
Definitions
Barrel terms
HBAR: Heavy BARrel,Heavy Barrelled AR, Heavy Barrelled Automatic Rifle, Heavy Barrel AssaultRifle
.223: .223 Remington, 5.56 x 45 mm NATO cartridge
9x19mm: 9 mm Parabellum cartridge
.22 LR: .22 Long Riflerimfire cartridge
1:7': Riflingin the barrel twists clockwise, with any one groove making a complete revolutionevery seven (7)
inches (178 mm).
1:9': Riflingin the barrel twists clockwise, with any one groove making a complete revolutionevery nine (9)
inches (229 mm).
1:10': Riflingin the barrel twists clockwise, with any one groove making a complete revolutionevery ten (10)
inches (254 mm).
1:12': Riflingin the barrel twists clockwise, with any one groove making a complete revolutionevery twelve
(12) inches (305 mm).
Barrel contour/slip ring/handguard terms
Standard: Original thin barrelstyle. Did not stand up to prolonged firing very well giving reducedaccuracy.
A2: Later style of barrel that was tapered at the front sight to thicken theexposed barrel. Apparently to
strengthen the barrel to avoid bending when G.I.'s used it as a pry bar.
HBAR: Lateststyle of barrel that is the same thickness the enitre length through, ratherthan just the exposed
section. Stands up to heat well and gives better accuracy.
HBAR
stepped: New barrel for the M4 carbine designed specifically with a 'step' to accomodatethe M203 grenade
launcher.
Straight: Slip ringretainer between the handguard and the upper receiver that has a straightcylindrical shape.
Typically found only on early AR-15 and M-16 rifles with A1 upper receivers.
Tapered: Slip ring retainer between the handguard and the upper receiver that hasa slight conical shape. Used on
all new AR-15 and M-16 rifles.
Smooth
triangular: The original handguard usedon early AR-15 and M-16 rifles. Still commonly seen today, not usedon
newer rifles. The handguard is a smoothened triangle shape with vent holesat the top.
Ribbed
cylindrical:Newerhandguard used on all modern AR-15 and M-16 rifles. Cylindrical ratherthan triangular, it has
vertical ribs along the entire length of the handguard for better grip. Vent holes are along the top and
bottom.
Ribbed
shorty:Identicalto the Ribbed cylindrical handguard found on modern AR-15 and M-16 rifles,the shorty
handguard differs only by being shorter to accomodate shorter barrel lengths.
Smooth
cylindrical: Special handguard found only on the7' barrel of the 9mm Model 633. It has no ribs and is smooth
along its entire length.
Square
LMG:Bulky square handguard used on the M16A2 MachineGun to vent heat as efficiently and quickly as
possible. Has several holes in the top and bottom to accomodate specialattachments such as a vertical
foregrip and carrying handle.
Flash hider terms
3-prong: Vietnam-era flash suppressorwith three slits and an open front end. Soon changed to closed endafter
vegetation frequently got caught in the prongs.
Birdcage:Newerstyle of flash suppressor that has six openings with a closed front end. Changed to A2-style to
prevent dust kickup when firing.
A2-style:LatestColt flash suppressor that has five openings (two to either side, two diagonallyupwards, and one up) and
a closedfront end. The lack of holes in thebottom of the suppressor avoids kicking up dust when firing.
Vortex: A highly efficient flash suppressor that eliminates all muzzle flash evenfrom very short barrels. Typically
four-pronged and 1/2' longer than the 3-prong suppressor. Newer modelshave the prongs twisted
slightly counterclockwise.
Sight style terms
A1: Original style rear sight that was adjustable for windage only. Adjustmentsrequired the use of a tool or
bullet tip. Flip-type aperatures for short and long-range shootingare provided, the ranges depending on
the firearm.
A2:Newer style rear sight that is adjustable forwindage and elevation up to 800 meters, and requires no tools
for adjustment.
Receiver terms
A1: The original, non-reinforced, slab-sided lower receiver with the exposed magazine release button. Easily recognizable by the smooth right side. Usually accompanied by a straight pistol grip.
A2: Newerlower receiver with reinforcing around the magazine well and a 'fence'around the magazine release button.
Flattop: New style of receiver that lacks the carry handle. Allows for themounting of a wide variety of optical
sighting devices and accessories.
Grip terms
Straight: First production pistol grip. Was straight and had no notches or contours for the fingers or the hand.
Grooved: Later production pistol grip, nowstandard on all new AR-15 and M-16 rifles. Slightly thicker gripwith
a notch for the middle finger for a better grasp.
Colt Ar-15 A2 Gov T Carbine Serial Numbers List
Colt Ar-15 A2 Gov't Carbine Serial Numbers
| This page copyright (C) Andrew Krywonizka, 1998-1999. All rights reserved. This page may not be reproduced, mechanically or electronically or otherwise, without express written consent from the author. The Colt logo is a registered trademark of Colt's Manufacturing Company, Inc. |
Last Modified on September 24, 1999
aalbert@biggerhammer.net