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SIG SAUER SIG MCX .300 AAC Blackout Upper Receiver WUAMCX-6B-300B-BLK-TAP

Sig Sauer SIG MCX Upper Receiver, .300 AAC Blackout, 6.75 in, Tapered Lug, Black, WUAMCX-6B-300B-BLK-TAP
Sig Sauer SIG MCX Upper Receiver, .300 AAC Blackout, 6.75 in, Tapered Lug, Black, WUAMCX-6B-300B-BLK-TAP
1 of 1 images
Sig Sauer SIG MCX Upper Receiver, .300 AAC Blackout, 6.75 in, Tapered Lug, Black, WUAMCX-6B-300B-BLK-TAP

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Questions & Answers
Will this fit and work with the Sig M400 Tread?

It will fit on it but it won't run without the sig mcx adapter.

by DJ, Verified Owner, August 4, 2022
See 1 More Answer
Does this come as a kit with the duo trigger and rear folding stock adapter? Expert Answer

Unfortunately, the SIG SAUER SIG MCX .300 AAC Blackout Upper Receiver is no longer available. However, we do carry the SIG SAUER Sig MCX Upper Receiver Assembly, found by using the link below:
https://www.opticsplanet.com/sig-sauer-sig-mcx-upper-receiver-assemebly-m-lok.html

by Ethan, Gear Expert, August 12, 2022
View All Q&A You Have a Question? Ask!
Caliber:
.300 AAC Blackout
Barrel Length:
6.75 in
Color:
Black
Additional Features:
Tapered Lug
Condition:
New

Code: SD9-URC-E64180F2-WUAMCX-6B-300B-BLK-TAP

MPN: WUAMCX-6B-300B-BLK-TAP

UPC: 798681579419

Product No Longer Available

Product Info for SIG SAUER SIG MCX .300 AAC Blackout Upper Receiver

Upper, Sigmcx, 300 Blk, 6.75in, Blk, Ar Conversion, Tapered Lug, Mlok, Worldimage

Package Contents:

  • SIG SAUER Upper, Sigmcx

Ammunition

1–39 / 39
Previous
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Freedom Munitions .300 Blackout 147 Grain Full Metal Jacket Brass Rifle Ammunition
Freedom Munitions .300 Blackout 147 Grain Full Metal Jacket Brass Rifle Ammunition
(5)
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Super Vel Ammunition 300 Blackout 150 grain Full Metal Jacket Brass Cased Rifle Ammunition
Super Vel Ammunition 300 Blackout 150 grain Full Metal Jacket Brass Cased Rifle Ammunition
As Low As (Save Up to 20%)
$46.29
$0.82 - $0.93/Round
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Freedom Munitions .300 Blackout 150 Grain Full Metal Jacket Brass Rifle Ammunition
Freedom Munitions .300 Blackout 150 Grain Full Metal Jacket Brass Rifle Ammunition
(2)
As Low As (Save 12%)
$33.49
$0.66 - $0.67/Round
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Barnes Precision Match .300 AAC Blackout 125 grain Match Burner Open Tip Match Boat Tail Centerfire Rifle Ammunition
Barnes Precision Match .300 AAC Blackout 125 grain Match Burner Open Tip Match Boat Tail Centerfire Rifle Ammunition
(1)
As Low As (Save Up to 10%)
$39.79
$1.99 - $2.13/Round
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Hornady Frontier .300 AAC Blackout 125 Grain Full Metal Jacket Centerfire Rifle Ammunition
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(5)
As Low As (Save Up to 27%)
$23.69
$1.18 - $1.28/Round
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Best Rated
Barnes Vor-TxRifle Cartridges, .300 AAC Blackout, TAC-TX Flat Base, 110 Grain, 20 - Rounds, 21548
Barnes Vor-TxRifle Cartridges, .300 AAC Blackout, TAC-TX Flat Base, 110 Grain, 20 - Rounds, 21548
(7)
List: $48.99 (Save 16%)
$41.39
$2.07/Round
Remington .300 AAC Blackout 150 Grains Full Metal Jacketed Brass Centerfire Rifle Ammunition
Remington .300 AAC Blackout 150 Grains Full Metal Jacketed Brass Centerfire Rifle Ammunition
(2)
As Low As (Save Up to 10%)
$29.79
$1.49 - $1.62/Round
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On Sale
Armscor Precision Inc USA .300 AAC Blackout 147 Grain Full Metal Jacket Brass Cased Rifle Ammo, 20 Rounds, FAC300AAC-1N-20RD
Armscor Precision Inc USA .300 AAC Blackout 147 Grain Full Metal Jacket Brass Cased Rifle Ammo, 20 Rounds, FAC300AAC-1N-20RD
(13)
List: $23.99 (Save 42%)
$13.89
$0.69/Round
Fort Scott Munitions 300AAC BLACKOUT 190 Grain Centerfire Rifle Ammo, 20 Rounds, 300-190-SCV1SS
Fort Scott Munitions 300AAC BLACKOUT 190 Grain Centerfire Rifle Ammo, 20 Rounds, 300-190-SCV1SS
(4)
List: $38.15 (Save 10%)
$34.29
$1.71/Round
Nosler Match Grade .300 AAC Blackout 220 Grain Custom Competition Hollow Point Boat Tail Brass Cased Centerfire Rifle Ammo, 20 Rounds, 51275
Nosler Match Grade .300 AAC Blackout 220 Grain Custom Competition Hollow Point Boat Tail Brass Cased Centerfire Rifle Ammo, 20 Rounds, 51275
(3)
List: $44.95 (Save 15%)
$38.19
$1.91/Round
Barnes Vor-TxRifle Cartridges, .300 AAC Blackout, TAC-TX Boat Tail , 120 Grain, 20 - Rounds, 30827
Barnes Vor-TxRifle Cartridges, .300 AAC Blackout, TAC-TX Boat Tail , 120 Grain, 20 - Rounds, 30827
List: $48.99 (Save 16%)
$41.39
$2.07/Round
Sellier & Bellot eXergy .300 AAC Blackout 110 Grain Full Metal Jacket Brass Cased Rifle Ammo, 20 Rounds, SB300BLKXA
Sellier & Bellot eXergy .300 AAC Blackout 110 Grain Full Metal Jacket Brass Cased Rifle Ammo, 20 Rounds, SB300BLKXA
(3)
List: $28.65 (Save 35%)
$18.59
$0.93/Round
SinterFire Reduced Hazard .300 AAC Blackout 110 Grain Frangible Brass Cased Rifle Ammo, 50 Rounds, SF300BLK110RHA
SinterFire Reduced Hazard .300 AAC Blackout 110 Grain Frangible Brass Cased Rifle Ammo, 50 Rounds, SF300BLK110RHA
(3)
List: $50.69 (Save 20%)
$40.39
$0.81/Round
Wilson Combat Hornady ELD-M .300 AAC Blackout 208 Grain Brass Cased Pistol Ammo, 20 Round, A300BLK-208-ELDM-20RD
Wilson Combat Hornady ELD-M .300 AAC Blackout 208 Grain Brass Cased Pistol Ammo, 20 Round, A300BLK-208-ELDM-20RD
List: $39.95 (Save 12%)
$35.19
$1.76/Round
Hornady American Gunner .300 AAC Blackout 125 grain Hollow Point Brass Cased Centerfire Rifle Ammo, 50 Rounds, 80897
Hornady American Gunner .300 AAC Blackout 125 grain Hollow Point Brass Cased Centerfire Rifle Ammo, 50 Rounds, 80897
List: $95.35 (Save 28%)
$68.99
$1.38/Round
Best Rated
Barnes 300 AAC Blackout, 120 Grain, Jacketed Hollow Point/JHP, Brass Cased Centerfire Rifle Ammo, 20 Rounds, 32004
Barnes 300 AAC Blackout, 120 Grain, Jacketed Hollow Point/JHP, Brass Cased Centerfire Rifle Ammo, 20 Rounds, 32004
(6)
List: $27.99 (Save 10%)
$25.29
$1.26/Round
Wilson Combat Sierra .300 AAC Blackout 220 Grain Hollow Point Boat Tail Brass Cased Pistol Ammo, 20 Round, A300BLK-220-HPBT-20RD
Wilson Combat Sierra .300 AAC Blackout 220 Grain Hollow Point Boat Tail Brass Cased Pistol Ammo, 20 Round, A300BLK-220-HPBT-20RD
(1)
List: $44.95 (Save 12%)
$39.69
$1.98/Round
HSM 300BLK4N Match 300 Blackout 220 Gr Hollow Point Boat Tail HPBT
HSM 300BLK4N Match 300 Blackout 220 Gr Hollow Point Boat Tail HPBT
List: $61.49 (Save 38%)
$38.19
$1.91/Round
SinterFire GreenLine .300 AAC Blackout 110 Grain Frangible Brass Rifle Ammo, 50 Rounds, SF300BLK110GL-C
SinterFire GreenLine .300 AAC Blackout 110 Grain Frangible Brass Rifle Ammo, 50 Rounds, SF300BLK110GL-C
(1)
List: $52.79 (Save 20%)
$42.09
$0.84/Round
Hornady Ammo Custom, .300 Blackout, 110 Grain, Centerfire Rifle Ammo, CX Polymer Tip, 20 Rounds, 808794
Hornady Ammo Custom, .300 Blackout, 110 Grain, Centerfire Rifle Ammo, CX Polymer Tip, 20 Rounds, 808794
(4)
List: $50.84 (Save 34%)
$33.39
$1.67/Round
Nosler BTA Ballistic Tip Ammunition 300 Blackout 220 Grain Ballistic Tip Round Nose Brass Cased Centerfire Rifle Ammo, 20 Rounds, 61050
Nosler BTA Ballistic Tip Ammunition 300 Blackout 220 Grain Ballistic Tip Round Nose Brass Cased Centerfire Rifle Ammo, 20 Rounds, 61050
List: $48.95
$48.89
$2.44/Round
Federal Premium Power-Shok Copper .300 AAC Blackout 120 Grain Copper Hollow Point Centerfire Rifle Ammo, 20 Rounds, 300BLK120LFA
Federal Premium Power-Shok Copper .300 AAC Blackout 120 Grain Copper Hollow Point Centerfire Rifle Ammo, 20 Rounds, 300BLK120LFA
List: $47.99 (Save 29%)
$33.89
$1.69/Round
Barnes Precision Match .300 AAC Blackout 220 grain Jacketed Hollow Point Brass Cased Rifle Ammo, 20 Rounds, 32134
Barnes Precision Match .300 AAC Blackout 220 grain Jacketed Hollow Point Brass Cased Rifle Ammo, 20 Rounds, 32134
List: $45.99 (Save $1.40)
$44.59
$2.23/Round
Hornady Custom .300 AAC Blackout 135 grain Flex Tip eXpanding Brass Cased Centerfire Rifle Ammo, 20 Rounds, 80881
Hornady Custom .300 AAC Blackout 135 grain Flex Tip eXpanding Brass Cased Centerfire Rifle Ammo, 20 Rounds, 80881
(3)
List: $49.53 (Save 28%)
$35.49
$1.77/Round
Best Rated
Hornady Subsonic .300 AAC Blackout 190 grain Subsonic eXpanding Brass Cased Centerfire Rifle Ammo, 20 Rounds, 80877
Hornady Subsonic .300 AAC Blackout 190 grain Subsonic eXpanding Brass Cased Centerfire Rifle Ammo, 20 Rounds, 80877
(24)
List: $44.80 (Save 21%)
$35.59
$1.78/Round
Super Vel Ammunition 300 Blackout 200 grain Full Metal Jacket Brass Cased Rifle Ammunition
Super Vel Ammunition 300 Blackout 200 grain Full Metal Jacket Brass Cased Rifle Ammunition
As Low As (Save Up to 17%)
$57.89
$1.13 - $1.16/Round
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Veteran Ammo Defense .300 AAC Blackout 110 Grain Hollow Point Centerfire Pistol Ammo, 20 Rounds, HMBX-300-26
Veteran Ammo Defense .300 AAC Blackout 110 Grain Hollow Point Centerfire Pistol Ammo, 20 Rounds, HMBX-300-26
List: $53.49 (Save 23%)
$41.29
$2.06/Round
Best Rated
Winchester Super Suppressed .300 AAC Blackout 200 grain Full Metal Jacket Centerfire Rifle Ammo, 20 Rounds, SUP300BLK
Winchester Super Suppressed .300 AAC Blackout 200 grain Full Metal Jacket Centerfire Rifle Ammo, 20 Rounds, SUP300BLK
(19)
List: $34.99 (Save 48%)
$18.19
$0.91/Round
Veteran Ammo Defense .300 AAC Blackout 200 Grain Hollow Point Centerfire Pistol Ammo, 20 Rounds, HMBX-300-27
Veteran Ammo Defense .300 AAC Blackout 200 Grain Hollow Point Centerfire Pistol Ammo, 20 Rounds, HMBX-300-27
List: $59.99 (Save 19%)
$48.89
$2.44/Round
Best Rated
Hornady BLACK .300 AAC Blackout 110 grain V-MAX Brass Cased Centerfire Rifle Ammo, 20 Rounds, 80873
Hornady BLACK .300 AAC Blackout 110 grain V-MAX Brass Cased Centerfire Rifle Ammo, 20 Rounds, 80873
(10)
List: $42.47 (Save 21%)
$33.69
$1.68/Round
Remington .300 AAC Blackout UMC 220 Grain Open Tip Flat Base Brass Centerfire Rifle Ammunition
Remington .300 AAC Blackout UMC 220 Grain Open Tip Flat Base Brass Centerfire Rifle Ammunition
(3)
As Low As (Save 10%)
$279.29
$1.75/Round
See all 2 models
Freedom Munitions HUSH Subsonic .300 Blackout 220 Grain HPBT Brass Rifle Ammo, 50 Rounds, FMH300H220N50
Freedom Munitions HUSH Subsonic .300 Blackout 220 Grain HPBT Brass Rifle Ammo, 50 Rounds, FMH300H220N50
(1)
List: $63.19 (Save 12%)
$55.49
$1.11/Round
Remington UMC Rifle .300 AAC Blackout 220 Grain Open Tip Flat Base Centerfire Rifle Ammunition
Remington UMC Rifle .300 AAC Blackout 220 Grain Open Tip Flat Base Centerfire Rifle Ammunition
(1)
As Low As (Save 11%)
$34.89
$1.74 - $1.75/Round
See all 2 models
Sellier & Bellot .300 Aac Blackout Fmj Subsonic - SB300BLKSUBACS
Sellier & Bellot .300 Aac Blackout Fmj Subsonic - SB300BLKSUBACS
List: $1,132.00 (Save 17%)
$944.99
$0.94/Round
Magtech 300 Blackout 123 Grain Full Metal Jacket Brass Cased Rifle Ammo, 50 Rounds, 300BLKB
Magtech 300 Blackout 123 Grain Full Metal Jacket Brass Cased Rifle Ammo, 50 Rounds, 300BLKB
(1)
List: $46.29 (Save 10%)
$41.89
$0.84/Round
Best Rated
Hornady BLACK .300 AAC Blackout 208 grain A-MAX Brass Cased Centerfire Rifle Ammo, 20 Rounds, 80891
Hornady BLACK .300 AAC Blackout 208 grain A-MAX Brass Cased Centerfire Rifle Ammo, 20 Rounds, 80891
(7)
List: $42.92 (Save 21%)
$33.99
$1.70/Round
Hornady Frontier 300 Blackout 208 Grain FMJ Brass Cased Rifle Ammo, 20 Rounds, FR410
Hornady Frontier 300 Blackout 208 Grain FMJ Brass Cased Rifle Ammo, 20 Rounds, FR410
List: $36.25 (Save 21%)
$28.79
$1.44/Round
Freedom Munitions .300 Blackout 125 Grain Full Metal Jacket Brass Rifle Ammo, 50 Rounds, FM300F125N50
Freedom Munitions .300 Blackout 125 Grain Full Metal Jacket Brass Rifle Ammo, 50 Rounds, FM300F125N50
(1)
List: $37.19 (Save 12%)
$32.59
$0.65/Round
Newly Added
SIG SAUER .300 AAC Blackout 194 Grain Max Expansion Brass Cased Rifle Ammo, 20 Rounds, C300D2-20
SIG SAUER .300 AAC Blackout 194 Grain Max Expansion Brass Cased Rifle Ammo, 20 Rounds, C300D2-20
List: $79.99 (Save 10%)
$71.79
$3.59/Round
Next

Ammo Boxes

1–1 / 1
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MTM Ammo Can Tray for Metal Cans 30 Cal., Dark Earth, MAC30
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SIG SAUER SIG MCX .300 AAC Blackout Upper Receiver Unavailable & Discontinued Models

List of Unorderable Models

  • SIG SAUER SIG MCX Upper Receiver, .300 AAC Blackout, 6.75 in, Tapered Lug, Black, WUAMCX-6B-300B-BLK-TAP , MPN: WUAMCX-6B-300B-BLK-TAP , UPC: 798681579419 , Code: SD9-URC-E64180F2-WUAMCX-6B-300B-BLK-TAP
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