Bushmaster Upper Receiver Assemblies




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.450 Upper Receiver / Bbl. Assembly
New .450 Bushmaster Caliber. 20" or 16" w. Izzy Suppressor. Includes 4 Rd. Magazine. These uppers will mount right on your mil. spec. Lower. With a velocity of 2200 FPS, the Hornady 250 Gr. SST/FT bullet in the .450 Bushmaster "Thumper" is designed for all large North American game. Though not a long distance cartridge, accuracy has proved to be exceptional out to 200 yards with felt recoil similar to a 20 ga. shotgun. Tubular aluminum forends allow the barrel to free float from the nut forward, chrome lining in both bore and chamber makes for long barrel life and easy cleaning.

Options: 20" Barrel or 16" Barrel
Price: $843.57
Part No: F1007571
Quantity:
Currently
Out Of Stock.
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11.5" A2 Upper Receiver/Barrel Assembly
An ideal package for the Law Enforcement professional, its compact size offers easy handling in close quarters and squad cars. This assembly's short barrel length requires that these uppers be used on full automatics, or registered short barreled rifles or pistols. The A2 "Birdcage" Suppressor is standard with this assembly, but other flash suppressors are also available as factory installed options.

NOTE: This Upper Receiver/Barrel Assembly is legal for installation only on weapons registered as Short Barreled Rifles or Pistols.
Price: $599.46
Part No: F1007698
Quantity:
Currently
Out Of Stock.
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11.5" Upper Rec. / Bbl. Assembly with 5.5" Flash Suppressor
Our 5.5" CAR 15 Extended Flash Suppressor is pinned onto this 11.5" barrel, and welded to meet 16" total barrel length requirements.

Options: A2 or A3 Upper, A3 Upper with no Carry Handle
Price: $610.79
Part No: F1007427
Quantity:
Currently
Out Of Stock.
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11.5" Upper Rec. / Bbl. Assembly with 5.5" Flash Suppressor - No Bolt
Our 5.5" CAR 15 Extended Flash Suppressor is pinned onto this 11.5" barrel, and welded to meet 16" total barrel length requirements.

Options: A2 or A3 Upperm A3 Upper with No Carry Handle
Price: $451.14
Part No: F1007409
Quantity:
Currently
Out Of Stock.
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11.5" Upper Receiver/Barrel Assembly 1x7 Twist
An ideal package for the Law Enforcement professional, its compact size offers easy handling in close quarters and squad cars. This assembly's short barrel length requires that these uppers be used on full automatics, or registered short barreled rifles or pistols. Configurations with the A3 "flat-top" upper receiver are also available at no extra cost. The A2 "Birdcage" Suppressor is standard with this assembly, but other flash suppressors are also available as factory installed options.

NOTE: This Upper Receiver/Barrel Assembly is legal for installation only on weapons registered as Short Barreled Rifles or Pistols.

Options: A2 w/Lug or A2 w/o Lug, A3 w/Lug or A3 w/o Lug
Price: $727.18
Part No: F1007486
Quantity:
Currently
Out Of Stock.
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14.5" .223 Caliber Upper Receiver / Barrel Assembly
Bushmaster .223/5.56mm caliber 14.5" Chrome Lined M4 Profile Barrels with permanent Izzy Flash Suppressor. Total barrel length just over 16in makes this a BATF legal assembly.
1X9 Twist, A2 Front Sight, Flat-Top, A3 Carry Handle

Options: A3 or A2
Price: $769.41
Part No: F1007506
Quantity:
Currently
Out Of Stock.
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14.5" .223 Caliber Upper Receiver / Barrel Assembly - No Bolt
14.5" Chrome Lined M4 Profile Barrels with permanent Izzy Flash Suppressor. Total barrel length just over 16in makes this a BATF legal assembly.
Less Bolt, Carrier and Charging Handle.

Options: A3 or A2
Price: $605.64
Part No: F1007468
Quantity:
Currently
Out Of Stock.
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14.5" Bbl. M4 Type Upper Receiver/Barrel Assembly
One of our most popular Law Enforcement configurations, this light weight, chrome lined 14.5" barrel assembly has the "cutout" profile designed to mount the M203 Grenade Launcher.

Options: A2 or A3 Upper
Price: $626.24
Part No: F1007435
Quantity:
Currently
Out Of Stock.
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14.5" Heavy Barrel Upper Receiver / Bbl. Assembly
This lightweight carbine upper can be ordered with either the A2 Upper Receiver or the A3 "flat-top" style Upper.The 14.5" barrel length makes this Upper legal for use only on weapons registered as pistols, short-barreled rifles or full-automatic rifles. The chrome lined barrel is heavy profile in its full length, and the A2 birdcage suppressor is standard. Other flash suppressors / muzzle brakes are available as optional installations, and if permanently attached, and long enough to create a 16" overall barrel unit, this assembly would become legal for use on semi-automatic lowers.

Options: A2 or A3 Upper
Price: $599.46
Part No: F1007430
Quantity:
Currently
Out Of Stock.
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14.5" Heavy Barrel Upper Receiver / Bbl. Assembly No Bolt
This lightweight carbine upper can be ordered with either the A2 Upper Receiver or the A3 "flat-top" style Upper.The 14.5" barrel length makes this Upper legal for use only on weapons registered as pistols, short-barreled rifles or full-automatic rifles. The chrome lined barrel is heavy profile in its full length, and the A2 birdcage suppressor is standard. Other flash suppressors / muzzle brakes are available as optional installations, and if permanently attached, and long enough to create a 16" overall barrel unit, this assembly would become legal for use on semi-automatic lowers.

Options: A2 or A3 Upper
Price: $451.14
Part No: F1007411
Quantity:
Currently
Out Of Stock.
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16" Dissipator Upper Receiver/Barrel Assembly
In the unique Dissipator, gas block placement is under the rifle length handguards to offer reliable cycling, the accuaracy of the full sight radius, and cool operation.

Options: A2 w/Lug or A2 w/o Lug
Price: $642.72
Part No: F1007443
Quantity:
Currently
Out Of Stock.
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16" Dissipator upper Receiver/Barrel Assembly - No Bolt
In the unique Dissipator, gas block placement is under the rifle length handguards to offer reliable cycling, the accuaracy of the full sight radius, and cool operation.

Options: A2, A3 or A3 with no Carry Handle
Price: $584.01
Part No: F1007474
Quantity:
Currently
Out Of Stock.
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16" Heavy Carbine Upper Receiver/Barrel Assembly
Bushmaster's 16" chrome lined, heavy carbine barrels - headspaced, test fired, and ready for use - include short carbine handguards.

Options: A2, A3 or A3 with no Carry Handle
Price: $727.18
Part No: F1007514
Quantity:
Currently
Out Of Stock.
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16" Heavy Carbine Upper Receiver/Barrel Assembly No Bolt
Bushmaster's 16" chrome lined, heavy carbine barrels - headspaced, test fired, and ready for use - include short carbine handguards.

Options: A2, A3 or A3 with no Carry Handle
Price: $568.56
Part No: F1007473
Quantity:
Currently
Out Of Stock.
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16in Carbine M4 Type Upper Receiver.
One of our most popular configurations, this light weight, chrome lined 16" barrel assembly has the "cutout" profile designed to mount the M203 Grenade Launcher. The A2 configuration is shown - see Options for ordering A3 versions (flat-top receiver)
Price: $626.24
Part No: F1007445
Quantity:
Currently
Out Of Stock.
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16in Dissipator A3 Upper Receiver/Barrel Assembly
In the unique Dissipator, gas block placement is under the rifle length handguards to offer reliable cycling, the accuaracy of the full sight radius, and cool operation.

Options: A3 with or no Carry Handle, Bayonet Lug, w/o Bayonet Lug
Price: $748.81
Part No: F1007515
Quantity:
Currently
Out Of Stock.
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16in PostBan Carbine M4 Type Upper Receiver/Barrel Assembly
Price: $626.24
Part No: F1007610
Quantity:
Currently
Out Of Stock.
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20" Flat Top National Target Match
Rifled 1 turn in 9", these heavy profile, hard chrome lined barrels deliver Bushmaster accuracy for match competitors worldwide. The A3 Upper Receiver is complete (headspaced, test fired, and ready to snap onto your lower receiver) with charging handle, forward assist, ejection port cover, bolt, bolt carrier assembly and handguards

Options: A3 w/Lug or A3 w/o Lug
Price: $727.18
Part No: F1007525
Quantity:
Currently
Out Of Stock.
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20" Flat Top National Target Match No Bolt
Rifled 1 turn in 9", these heavy profile, hard chrome lined barrels deliver Bushmaster accuracy for match competitors worldwide. The A2 Upper Receiver is complete (headspaced, test fired, and ready to snap onto your lower receiver) with dual aperture rear sight, charging handle, forward assist, ejection port cover, bolt, bolt carrier assembly and handguards

Options: A3 w/Lug or A3 w/o Lug
Price: $562.38
Part No: F1007480
Quantity:
Currently
Out Of Stock.
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20" National Match Target Model Upper Receiver/Barrel Assembly
Rifled 1 turn in 9", these heavy profile, hard chrome lined barrels deliver Bushmaster accuracy for match competitors worldwide. The A2 Upper Receiver is complete (headspaced, test fired, and ready to snap onto your lower receiver) with dual aperture rear sight, charging handle, forward assist, ejection port cover, bolt, bolt carrier assembly and handguards. .

Options: 20" A2 w/Lug or 20" A2 w/o Lug, 24" A2 w/Lug or 24" A2 w/o Lug, 24" A3 w/Lug or 24" A3 w/o Lug
Price: $626.24
Part No: F1007449
Quantity:
Currently
Out Of Stock.
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20" Predator Upper Receiver/Barrel Assembly
Adapted from our very accurate and successful 24" Varminter, the Predator Upper Receiver/Barrel Assembly's 20" Fluted Extra Heavy Barrel is button rifled 1 x 8" to stabilize the heavier 69-77 grain bullets that a predator hunter/caller would choose for bigger varmints and predators. This superb barrel features fluting for increased cooling and weight reduction; an 11 degree competition crown; 1" diameter heavy profile under the handguard; custom match hybrid chamber with a tighter SAAMI Spec headspace from the shoulder of the chamber to the bolt face, and longer chamber throat or "Leade". This chamber accommodates 5.56mm ammunition without developing higher pressures encountered when firing 5.56mm ammo in a .223 chamber with shorter "Leade" (both calibers can be used safely). This Upper is sold complete with Bolt, Bolt Carrier and Charging Handle to ensure positive lockup between bolt and barrel extension. The Predator Upper also features a Vented Tubular Aluminum Free-Floater Forend with Bipod Stud (free-floats the barrel from the barrel nut forward) and B.M.A.S. 1/2" Mini-Risers to add scope height for correct sight picture and comfortable cheek weld.

Price: $822.97
Part No: F1007682
Quantity:
Currently
Out Of Stock.
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24" Varminter Upper Receiver/Barrel Assembly
This Assembly - from our very accurate Varminter - features a 24" Fluted Extra Heavy Barrel in 5.56mm/.223 Rem. caliber with 11 degree competition crown; heavyweight 1" diameter under the handguard; custom match hybrid chamber with a tighter SAAMI Spec headspace from the shoulder of the chamber to the bolt face, and longer chamber throat or "Leade". This accommodates 5.56mm ammunition without developing higher pressures encountered when firing 5.56mm ammo in a .223 chamber with shorter "Leade" (both calibers can be used safely). Rifling is 1 in 9" twist for optimum performance with most lighter bullet weight varmint cartridges, and the barrel is fluted to increase cooling and reduce weight. The Varminter Upper's shell ejection path has been modified to drop all your brass in the same place as a convenience for the reloader. A vented forend with bipod/sling stud installed, free-floats the barrel from the barrel nut forward and B.M.A.S. Mini-Risers add 1/2" to scope height for correct sight picture and comfortable cheek weld. This Upper is sold complete with Bolt, Bolt Carrier and Charging Handle to ensure positive lockup between bolt and barrel extension.

Price: $833.27
Part No: F1007687
Quantity:
Currently
Out Of Stock.
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6.8mm SPC Upper Receiver
6.8mm SPC Caliber * 16" M4 Profile Barrel * with 26 Round 6.8mm Magazine Mount a "Bushmaster of a higher caliber" on your existing Lower! The .270 cal. 6.8mm SPC (Special Purpose Cartridge) was developed for the military, but is now available commercially. Velocity averages a bit over 2600 FPS (with Hornady 115 Gr. V-Max), and the heavier bullet weights deliver a terminal energy capable of bringing down larger game. Complete 6.8mm SPC Barreled Upper Receiver Assemblies include one 26 Round Magazine.

Options:
A3 with Removable Carry Handle
A3 Less Carry Handle (Flat Top)
Price: $833.27
Part No: F1008522
Quantity:
Currently
Out Of Stock.
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A2 Stainless Steel-Barreled Upper Receiver/Barrel Assemblies
These Bushmaster Stainless Steel Barrels are machined to our strictest standards. We've had many requests to build Bushmaster accuracy in Stainless Steel configurations - just snap this complete assembly on your lower receiver and you're ready for the high power range. Assemblies are complete with Bushmaster forged Upper Receivers with Match Grade Polished Stainless Steel Barrels (1 in 9" right hand twist, button rifled).
Price: $679.80
Part No: F1007454
Quantity:
Currently
Out Of Stock.
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A3 11.5" Upper Rec. / Bbl. Assembly with 5.5" Flash Suppressor
Our 5.5" CAR 15 Extended Flash Suppressor is pinned onto this 11.5" barrel, and welded to meet 16" total barrel length requirements.

Note: The twist is 1x7 only

Price: $737.48
Part No: F1007488
Quantity:
Currently
Out Of Stock.
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Carbon 15 Flat-top Upper Reciever
Features an aluminum Picatinny Rail on a Carbon 15 Composite Upper; 5.56mm/.223 Rem. Caliber 16in M4 profile Chrome Lined Barrel with Izzy Compensator; Standard A2 Front Sight with square post (elevation adjustable); and carbine length handguards. This assembly is complete with Bolt, Carrier and Charging Handle.

Options: Carbon Flattop, Flattop Less, Model 4, Model 4 Less
Price: $642.72
Part No: F1004062
Quantity:
Currently
Out Of Stock.
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Modular Carbine Upper Receiver/Barrel Assembly
This is highly accessorized Upper Receiver/Barrel Assembly from our 16" Modular Carbine features a 16" Chrome Lined Chrome Moly Steel Fluted Barrel with Milled Gas Block. A Four Rail Free-Floater Tubular Forend combines with the A3 type "Flat-top" Upper Receiver to provide all the Picatinny rails necessary for mounting sights, scopes or accessories. Molded Rubber Sure Grip Rail Covers snap over the rail sections to add comfort and protection against heat buildup. The B.M.A.S. Rear Flip-up Sight is a dual aperture detachable unit with windage knob calibrated to 1/2 Minute of Adjustment. The B.M.A.S. Front Flip-up Sight clamps around the milled front gas block and incorporates an elevation adjustable front sight post - all ready for your lower receiver.

Options: Modular Carbine, Modular Carbine w/o Bayonet Lug
Price: $1,050.60
Part No: F1007565
Quantity:
Currently
Out Of Stock.
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Stainless Steel-Barreled Upper Receiver/Barrel Assemblies
These Bushmaster Stainless Steel Barrels are machined to our strictest standards. We’ve had many requests to build Bushmaster accuracy in Stainless Steel configurations - just snap this complete assembly on your lower receiver and you're ready for the high power range. Assemblies are complete with Bushmaster forged Upper Receivers with Match Grade Polished Stainless Steel Barrels (1 in 9" right hand twist, button rifled). 20" A2 Fixed Carry Handle Stainless Steel Bbl. Target Model Upper Receiver/Barrel Assembly (BURA2B 20SS) - with bayonet lug, A2 flash suppressor (PURA2B 20SS) - with crowned muzzle/no lug

20" A3 Removable Carry Handle Staniless Steel Bbl. Target Model Upper Receiver Assembly (BURA3B 20SS) with bayonet lug, A2 fash suppressor (PURA3B 20SS) - with crowned muzzle/no lug
Price: $674.65
Part No: F1007621
Quantity:
Currently
Out Of Stock.
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Upper with Removable Carry Handle
One of our most popular configurations, this light weight, chrome lined 16” barrel assembly has the “cutout” profile designed to mount the M203 Grenade Launcher. The A3 configuration is shown - see Options for ordering A2 versions (flat-top receiver)

Options: A2, A3 or A3 with no Carry Handle
Price: $716.00
Part No: BURA3B 16M4
Quantity:
Currently
Out Of Stock.
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Upper with Solid Fixed Carry Handle
One of our most popular configurations, this light weight, chrome lined 16" barrel assembly has the “cutout” profile designed to mount the M203 Grenade Launcher. The A3 configuration is shown - see Options for ordering A2 versions (flat-top receiver)

Options: A2, A3 or A3 with no Carry Handle
Price: $737.48
Part No: F1007519
Quantity:
Currently
Out Of Stock.
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Upper with Solid Fixed Carry Handle - No Bolt
One of our most popular configurations, this light weight, chrome lined 16" barrel assembly has the “cutout” profile designed to mount the M203 Grenade Launcher.

Options: A2, A3 or A3 with no Carry Handle
Price: $578.86
Part No: F1007478
Quantity:
Currently
Out Of Stock.
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V Match Upper Receiver/Barrel Assembly
These assemblies are defined by the "flat-top" Upper Receiver and a hard anodized, tubular, aluminum free-floater forend to offer accuracy and sight mounting versatility. Specify full or "milled" front sight base (milled shown), and threaded or crowned muzzle. Includes bayo. lug, threaded muzzle, A2 flash suppressor.

Options: 16", 20" or 24" Barrel, with or without Bolt, Carrier and Charging Handle
Price: $663.32
Part No: F1007560
Quantity:
Currently
Out Of Stock.
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V Match Upper Receiver/Barrel Assembly Less Bolt, Bolt Carrier Assembly and Charging Handle
These assemblies are defined by the flat-top Upper Receiver and a hard anodized, tubular, aluminum free-floater forend to offer accuracy and sight mounting versatility. Specify full or milled front sight base (milled shown), and threaded or crowned muzzle. Includes bayo. lug, threaded muzzle, A2 flash suppressor. Does not include: Bolt, Bolt Carrier Assembly and Charging Handle.
Options:

20" or 24" Barrels, With and Without Bayonet Lug or 20" Barrel Less Bolt With or Without Lug
Price: $499.55
Part No: F1007546
Quantity:
Currently
Out Of Stock.
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Varminter Special Upper Receiver/Stainless Steel Barrel Assembly
This assembly features a brush finished 24" Barrel machined of 416 Stainless Steel (button rifled 1 in 9") as used on our Stainless Varmint Special Rifle. It includes a Free-floater Vented Tubular Forend with Bipod / Sling Stud installed, 1/2" B.M.A.S. Mini-Risers - with Bolt, Carrier, and Charging Handle - all ready for your lower.

Options: Same Assembly without Bolt, Bolt Carrier Assembly and Charging Handle

Price: $833.27
Part No: F1007684
Quantity:
Currently
Out Of Stock.
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PLEASE NOTE: A Federal Firearms License is REQUIRED for the purchase of any Complete Weapon or Lower Receiver. Your order will not be processed without it. See the Dealer Locator for your nearest Bushmaster Dealer. Any other firearms parts or accessories shown in this website may be purchased directly.