Colt M16 Rifle Models

Courtesy Janes Infantry Weapons 

 

Model No. 
Model Name 
Caliber 
Barrel Length (in) 
Barrel Contour 
Barrel Twist
Weight (lbs) 
Forward Assist? 
Bayonet Lug?
Case Deflect?
Lower receiver
Rear Sight
Grip
Flash Hider
Barrel Slipring
Hndgrd
Fire Control
Added
Dropped
Comments
R6000 AR-15 Sporter
(SP1)		 .223 20 Standard  1:12" 7.5 No Yes No A1  A1 Straight  3-prong  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  7.62x39  16 HBAR 1:12" 7.5 Yes No Yes A2 A2   A2 Tapered Ribbed shorty  Safe, semiautomatic  1993 ---  
R6850DC Sporter Conversion Kit  7.62x39   16 HBAR 1:12" 4.2 Yes No Yes --- none   A2 Tapered Ribbed shorty  Safe, semiautomatic  1993 --- Flattop
R6851DC Sporter Conversion Kit  7.62x39   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      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      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      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      Flip-down front sight on 7" model 
701 M16A2 Rifle .223 20 HBAR 1:7" 7.9 Yes Yes Yes A2 A2 Grooved A2 Tapered Ribbed cylindrical  Safe, semiautomatic, full automatic      
705 M16A2 Rifle .223 20 HBAR 1:7" 7.9 Yes Yes Yes A2 A2 Grooved A2 Tapered Ribbed cylindrical  Safe, semiautomatic, 3-shot burst      Standard U.S. Military service rifle
715 M16A2 Rifle .223 20 HBAR 1:7" 7.9 Yes Yes Yes A2 A1 Grooved  A2 Tapered Ribbed cylindrical Safe, semiautomatic, full automatic      
719 M16A2 Rifle .223 20 HBAR 1:7" 7.9 Yes Yes Yes A2 A1 Grooved  A2 Tapered  Ribbed cylindrical Safe, semiautomatic, 3-shot burst       
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      
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       
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      
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      
750 M16A2 Light Machine Gun  .223 20 MG HBAR  1:7" 12.8 No No Yes A2 A2 Grooved A2 Tapered Square LMG Safe, full automatic      Bipod, front grip, carry handle, fires from open bolt 
Sources: American Rifleman, June 1993, page 80; Colt Data sheets for the M16 Family of Weapons, Colt's Manufacturing Company, Inc.

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.

 

Model 
Number 

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 forward assist.

Colt AR-15
Property of US  Gov't
Cal. .223
Model 02
Serial 0000000

 

603

M16A1

M16A1 rifle. Originally the XM16E1. Standard US Government model 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 forward assist.

Property of US Gov't
M16 Cal 5.56mm
0000000

 

605A

 

M16 carbine. Carbine version of M16A1 rifle with forward assist and fixed buttstock.

 

 

605B

 

M16 carbine. Same as Model 605A but with additional three-round burst 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 assist and 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 fixed tubular 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" (254 mm) barrel.

Property of US Gov't
SMG 5.56mm
0000000

 

610B

 

XM177E1 submachine gun for US Air Force with addition of 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 611 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.

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 forward assist.

Mod 614 Cal 5.56mm
0000000

 

614S

AR-15

M16 rifle. Export version of Model 614 license produced by Chartered Industries of Singapore.

C I S
Made in Singapore by Chartered Industries of Singapore Limited
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 Model 603.

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 assist and 11.5" barrel.

 

 

633

 

9 mm submachine gun with 7" (178 mm) barrel and mechanical buffer.

 

 

633HB

 

9 mm submachine gun with 7" (178 mm) barrel and hydraulic buffer.

 

 

634

 

9 mm submachine gun with 10.5" (267 mm) barrel, without forward assist.

 

 

635

 

9 mm submachine gun with 10.5" (267 mm) barrel, without forward 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 forward assist.

Mod 640 Cal 5.56mm
0000000

 

645

 

M16A2 rifle. Standard US Government model with revised 1 in 7" (1 in 177.8 mm) rifling, 20" (508 mm) barrel and new rear sight.

 

 

645E

 

M16A2 rifle 'Enhanced'. Modified M16A2 with removable carrying handle for optical sight mounting and flip-up front sight.

 

 

649

S.M.G.

Sumachine gun. For US Air Force, with 14" (356 mm) barrel and 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) barrel and full size stock.

 

 

652

 

M16A1 carbine. Export model with 14.5" (368 mm) barrel and full size stock, but without forward assist.

 

 

653

 

M16A1 carbine. Export model with 14.5" (368 mm) barrel and sliding stock.

 

 

653P

 

M16A1 carbine. Export model with 14.5" (368 mm) barrel and 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. Fitted with 14.5" (368 mm) barrel and sliding stock.

 

 

655

 

M16A1 sniper rifle. Experimental model with high profile upper receiver.

 

 

656

 

M16A1 sniper rifle. Experimental model with low profile upper receiver and Sionics suppressor.

 

 

701

 

M16A2 rifle. Export model with full automatic in place of three-round burst limiter.

 

 

702

 

M16A2 rifle. Export model for United Arab Emirates with M16A1 rear sights and full automatic in place of three-round burst limiter.

 

 

703

 

M16A2 rifle. Export model for the United Arab Emirates with M16A1 barrel profile and full automatic in place of three-round burst limiter.

 

 

705

 

M16A2 rifle. Export model with full automatic in place of three-round burst limiter.  Also known as M16A2E3.

 

 

707

 

M16A2 rifle. Export model with three-shot burst limiter and M16A1 barrel profile.

 

 

711

 

M16A2 rifle. Export model with M16A1 rear sight and M16A1 barrel profile.

 

 

715

 

M16A2 rifle. Canadian version of M16A2 rifle known as C7 with M16A1 rear sight and M16A2 barrel. License produced by Diemaco.

 

 

719

 

M16A2 rifle. Version of Model 715 produced by Colt with three-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 and US Army Delta Force. With M16A1 rear sight, 14.5" (370 mm) barrel and full automatic fire capability.

 

 

725

 

M16A2 carbine. Canadian version of M16A2 carbine known as C8 with M16A1 rear sight and M16A2 barrel. License produced by Diemaco.

 

 

725A

 

M16A2 carbine. Export version of the M16A2 carbine produced by Colt for United Arab Emirates with M16A1 barrel profile.

 

 

725B

 

M16A2 carbine. Export version of M16A2 carbine with M16A2 barrel.

 

 

727

 

M16A2 carbine. Carbine with full automatic fire feature produced for (among others) the US Navy. With 14.5" (370 mm) barrel.

 

 

733

 

M16A2 Commando. Short-barrelled model with full automatic fire, 11.5" (290 mm) barrel and M16A1 rear sight.

 

 

733A

 

M16A2 Commando. Short-barrelled model with three-round burst limiter in place of full automatic fire, 11.5" (290 mm) barrel and M16A1 rear sight.

 

 

735

 

M16A2 Commando. Similar to Model 733 but with three-round burst limiter.

 

 

737

 

M16A2 Heavy Barrel Assault Rifle (HBAR). With M16A1 rear sight.

 

 

741

 

M16A2 Heavy Barrel Assault Rifle (HBAR). As Model 737 but 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 rail under carrying handle. Fully automatic.

 

 

905

 

M16A3 rifle. Similar to Model 705 but with flat top rail under carrying handle. Three-round burst limiter.

 

 

925

 

M16A3 rifle. Similar to Model 725 but with flat top rail under carrying handle. Three-round burst limiter.

 

 

927

 

M4A1 carbine. Originally known as M16A3 carbine. Similar to 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 Model 741 but with flat top rail under carrying handle. Semi and fully automatic.

 

 

942

 

M16A3 Squad Automatic Weapon (SAW). Similar to Model 741 but with flat top rail under carrying handle. Fully automatic only.

 

 

950

 

M16A3 Squad Automatic Weapon (SAW). Similar to Model 741 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 Assault Rifle
.223:          .223 Remington, 5.56 x 45 mm NATO cartridge
9x19mm:   9 mm Parabellum cartridge
.22 LR:     .22 Long Rifle rimfire cartridge
1:7":        Rifling in the barrel twists clockwise, with any one groove making a complete revolution every seven (7)
                  inches (178 mm).
1:9":        Rifling in the barrel twists clockwise, with any one groove making a complete revolution every nine (9)
                  inches (229 mm).
1:10":       Rifling in the barrel twists clockwise, with any one groove making a complete revolution every ten (10)
                  inches (254 mm).
1:12":       Rifling in the barrel twists clockwise, with any one groove making a complete revolution every twelve
                  (12) inches (305 mm).

Barrel contour/slip ring/handguard terms

Standard:    Original thin barrel style.  Did not stand up to prolonged firing very well giving reduced accuracy.
A2:               Later style of barrel that was tapered at the front sight to thicken the exposed barrel.  Apparently to
                     strengthen the barrel to avoid bending when G.I.'s used it as a pry bar.
HBAR:        Latest style of barrel that is the same thickness the enitre length through, rather than 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 accomodate the M203 grenade
                     launcher.
Straight:      Slip ring retainer between the handguard and the upper receiver that has a straight cylindrical 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 has a slight conical shape. Used on
                     all new AR-15 and M-16 rifles.
Smooth
triangular:  The original handguard used on early AR-15 and M-16 rifles.  Still commonly seen today, not used on
                    newer rifles. The handguard is a smoothened triangle shape with vent holes at the top.
Ribbed
cylindrical: Newer handguard used on all modern AR-15 and M-16 rifles.  Cylindrical rather than 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:       Identical to 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 the 7" 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 Machine Gun to vent heat as efficiently and quickly as
                   possible.  Has several holes in the top and bottom to accomodate special attachments such as a vertical
                   foregrip and carrying handle.

Flash hider terms

3-prong:   Vietnam-era flash suppressor with three slits and an open front end.  Soon changed to closed end after
                  vegetation frequently got caught in the prongs.
Birdcage: Newer style of flash suppressor that has six openings with a closed front end.  Changed to A2-style to
                  prevent dust kickup when firing.
A2-style:  Latest Colt flash suppressor that has five openings (two to either side, two diagonally upwards, and one up) and
                  a closed front end.  The lack of holes in the bottom of the suppressor avoids kicking up dust when firing.
Vortex:     A highly efficient flash suppressor that eliminates all muzzle flash even from very short barrels. Typically
                  four-pronged and 1/2" longer than the 3-prong suppressor.  Newer models have the prongs twisted
                  slightly counterclockwise.

Sight style terms

A1:            Original style rear sight that was adjustable for windage only.  Adjustments required the use of a tool or
                  bullet tip.  Flip-type aperatures for short and long-range shooting are provided, the ranges depending on
                  the firearm.
A2:            Newer style rear sight that is adjustable for windage 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:            Newer lower 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 the mounting 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, now standard on all new AR-15 and M-16 rifles.  Slightly thicker grip with
                 a notch for the middle finger for a better grasp.