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CMMG, Inc MK4 RCE Upper Group 5.56mm, 16 in 55B5949

CMMG, Inc MK4 RCE Upper Group 5.56mm, 16in, Barrel, Black, 55B5949
CMMG, Inc MK4 RCE Upper Group 5.56mm, 16in, Barrel, Black, 55B5949
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CMMG, Inc MK4 RCE Upper Group 5.56mm, 16in, Barrel, Black, 55B5949

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Questions & Answers
Customer Reviews
Helpful Positive Review
Awesome upper by Instructor, Verified Owner, May 9, 2018
Love this upper.. worked flawlessly from the beginning to the time I departed the range... I consistently shoot two inch groups with this gun and if I had a better scope I am sure I could do much better... this thing is a tack driver
3/3 found this helpful
Read 1 Review

Product Discontinued by Manufacturer

CMMG, Inc MK4 RCE Upper Group 5.56mm, 16 in has been discontinued by CMMG and is no longer available. Our product experts have helped us select these available replacements below.You can also explore other items in the Gun Parts, AR 15 Parts, Rifle Parts, AR15 Upper Receivers yourself to try and find the perfect replacement for you!

Product Info for CMMG, Inc MK4 RCE Upper Group 5.56mm, 16 in

Features a 16 inch 416 stainless steel medium taper profile barrel, CMMG's own SV muzzle brake and RKM14 KeyMod hand guard.image

Ammunition

1–38 / 38
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10% Coupon
PMC Ammunition X-TAC Light Armor Piercing 5.56x45mm NATO 62 Grain Brass Cased Centerfire Rifle Ammunition
PMC Ammunition X-TAC Light Armor Piercing 5.56x45mm NATO 62 Grain Brass Cased Centerfire Rifle Ammunition
(108)
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$0.56 - $0.71/Round
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Hornady BLACK 5.56x45mm NATO 75 Grain InterLock HD SBR Centerfire Rifle Ammunition
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(20)
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$28.99
$1.37 - $1.45/Round
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Blazin' Deal
Aguila Ammunition 5.56x45mm NATO Ammo 55 Grain Full Metal Jacket Brass Cased Rifle Ammunition
Aguila Ammunition 5.56x45mm NATO Ammo 55 Grain Full Metal Jacket Brass Cased Rifle Ammunition
(12)
As Low As (Save Up to 37%)
$18.59
$0.42 - $0.62/Round
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Hornady Frontier 5.56x45mm NATO 62 Grain Full Metal Jacket Centerfire Rifle Ammunition
Hornady Frontier 5.56x45mm NATO 62 Grain Full Metal Jacket Centerfire Rifle Ammunition
(2)
As Low As (Save Up to 32%)
$11.99
$0.60 - $0.65/Round
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Freedom Munitions 5.56x45mm NATO 55 Grain Full Metal Jacket Brass Rifle Ammunition
Freedom Munitions 5.56x45mm NATO 55 Grain Full Metal Jacket Brass Rifle Ammunition
As Low As (Save Up to 19%)
$26.99
$0.54 - $0.58/Round
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Hornady BLACK 5.56x45mm NATO 62 grain Full Metal Jacket Brass Cased Centerfire Rifle Ammo, 20 Rounds, 81263
Hornady BLACK 5.56x45mm NATO 62 grain Full Metal Jacket Brass Cased Centerfire Rifle Ammo, 20 Rounds, 81263
(7)
List: $24.99 (Save 20%)
$19.99
$1.00/Round
Hornady Frontier 5.56x45mm NATO 55 Grain Hollow Point Centerfire Rifle Ammunition
Hornady Frontier 5.56x45mm NATO 55 Grain Hollow Point Centerfire Rifle Ammunition
(3)
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$32.19
$0.64 - $0.68/Round
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Hornady Superformance 5.56x45mm NATO 75 grain Boat-Tail Hollow Point Match Brass Cased Centerfire Rifle Ammo, 20 Rounds, 81264
Hornady Superformance 5.56x45mm NATO 75 grain Boat-Tail Hollow Point Match Brass Cased Centerfire Rifle Ammo, 20 Rounds, 81264
(8)
List: $41.40 (Save 30%)
$28.99
$1.45/Round
PMC 556M55BP Battle Pack 5.56 NATO 62 Gr Light Armor Piercing LAP
PMC 556M55BP Battle Pack 5.56 NATO 62 Gr Light Armor Piercing LAP
List: $89.00 (Save $4.01)
$84.99
$0.71/Round
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Barnes Vor-TxRifle Cartridges, 5.56x45mm NATO, TSX Boat Tail, 70 Grain, 20 - Rounds, *31191
Barnes Vor-TxRifle Cartridges, 5.56x45mm NATO, TSX Boat Tail, 70 Grain, 20 - Rounds, *31191
(14)
List: $40.99 (Save $1.20)
$39.79
$1.99/Round
First Breach 5.56 NATO 55 Grain Full Metal Jacket Boattail New C220 Brass Cased Rifle Ammo, 1000 Rounds, 50009
First Breach 5.56 NATO 55 Grain Full Metal Jacket Boattail New C220 Brass Cased Rifle Ammo, 1000 Rounds, 50009
(1)
List: $525.00 (Save $27.31)
$497.69
$0.50/Round
PMC 556XBP Battle Pack 5.56 NATO 55 Gr Full Metal Jacket Boat Tail FMJBT
PMC 556XBP Battle Pack 5.56 NATO 55 Gr Full Metal Jacket Boat Tail FMJBT
(1)
List: $144.00 (Save 14%)
$123.99
$0.62/Round
Hornady Superfomance 5.56 Nato 55 Grain Copper Solid CX Brass Cased Centerfire Rifle Ammo, 20 Rounds, 812544
Hornady Superfomance 5.56 Nato 55 Grain Copper Solid CX Brass Cased Centerfire Rifle Ammo, 20 Rounds, 812544
(3)
List: $46.61 (Save 34%)
$30.99
$1.55/Round
First Breach 5.56 NATO 55 Grain Full Metal Jacket Boattail New C220 Brass Cased Rifle Ammo, 20 Rounds, 556 55 loaded
First Breach 5.56 NATO 55 Grain Full Metal Jacket Boattail New C220 Brass Cased Rifle Ammo, 20 Rounds, 556 55 loaded
(1)
List: $19.99 (Save 42%)
$11.69
$0.58/Round
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Barnes Precision 5.56x45mm NATO 85 grain Burner Open Tip Match Boat Tail Centerfire Rifle Ammo, 20 Rounds, *30848
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(5)
List: $57.49 (Save 17%)
$47.99
$2.40/Round
PPU PPRM5561M 5.56X45 55 FMJBT RNGMSTR
PPU PPRM5561M 5.56X45 55 FMJBT RNGMSTR
List: $806.89 (Save $52.00)
$754.89
$0.75/Round
SIG SAUER Marskman 5.56x45mm NATO, 77 Grain, Elite Open Tip Match, Centerfire Rifle Ammo, 20 Rounds, E556M420
SIG SAUER Marskman 5.56x45mm NATO, 77 Grain, Elite Open Tip Match, Centerfire Rifle Ammo, 20 Rounds, E556M420
List: $52.49 (Save 37%)
$33.29
$1.66/Round
Atomic Ammunition Atomic Ammo 5.56x45 500 Rounds 62gr. Hornady Fmj Bulk-pack
Atomic Ammunition Atomic Ammo 5.56x45 500 Rounds 62gr. Hornady Fmj Bulk-pack
List: $629.99 (Save 10%)
$568.29
$1.14/Round
PMC Ammunition X-Tac 5.56x45mm NATO 55 Grain Full Metal Jacket Rifle Ammo, Metal Box, 840 Rounds, 1102741
PMC Ammunition X-Tac 5.56x45mm NATO 55 Grain Full Metal Jacket Rifle Ammo, Metal Box, 840 Rounds, 1102741
List: $632.49 (Save $49.50)
$582.99
$0.69/Each
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Hornady Frontier 5.56x45mm NATO 68 grain Boat-Tail Hollow Point Brass Cased Centerfire Rifle Ammo, 20 Rounds, FR310
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(14)
List: $19.60 (Save 21%)
$15.49
$0.77/Round
Best Rated
Hornady Frontier 5.56x45mm NATO 55 Grain Full Metal Jacket Brass Rifle Ammunition
Hornady Frontier 5.56x45mm NATO 55 Grain Full Metal Jacket Brass Rifle Ammunition
(41)
As Low As (Save 21%)
$12.49
$0.62 - $0.63/Round
See all 3 models
Veteran Ammo Defense 5.56x45mm NATO 62 Grain Hollow Point Centerfire Pistol Ammo, 20 Rounds, HMBX-556-24
Veteran Ammo Defense 5.56x45mm NATO 62 Grain Hollow Point Centerfire Pistol Ammo, 20 Rounds, HMBX-556-24
List: $49.99 (Save 24%)
$38.09
$1.90/Round
Best Rated
Hornady Frontier 5.56x45mm NATO 75 grain Boat Tail Hollow Point (BTHP) Brass Centerfire Rifle Ammunition
Hornady Frontier 5.56x45mm NATO 75 grain Boat Tail Hollow Point (BTHP) Brass Centerfire Rifle Ammunition
(28)
As Low As (Save Up to $7.50)
$26.99
$1.28 - $1.35/Round
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Best Rated
PMC Ammunition X-TAC, 5.56x45mm NATO, 55 grain, Full Metal Jacket, Brass, Centerfire Rifle Ammo, 20, 556X
PMC Ammunition X-TAC, 5.56x45mm NATO, 55 grain, Full Metal Jacket, Brass, Centerfire Rifle Ammo, 20, 556X
(63)
List: $15.99 (Save 31%)
$10.99
$0.55/Round
PPU 5.56x45mm NATO 0 grain Brass Cased Blank Ammo, 20 Rounds, PPB556
PPU 5.56x45mm NATO 0 grain Brass Cased Blank Ammo, 20 Rounds, PPB556
List: $22.49 (Save 32%)
$15.19
$0.76/Round
Veteran Ammo Defense 5.56x45mm NATO 62 Grain Full Metal Jacket Centerfire Pistol Ammo, 20 Rounds, HMBX-556-25
Veteran Ammo Defense 5.56x45mm NATO 62 Grain Full Metal Jacket Centerfire Pistol Ammo, 20 Rounds, HMBX-556-25
List: $49.99 (Save 23%)
$38.69
$1.93/Round
Best Rated
Winchester USA 5.56x45mm NATO 55 grain Ball (M193) Full Metal Jacket Brass Centerfire Rifle Ammunition
Winchester USA 5.56x45mm NATO 55 grain Ball (M193) Full Metal Jacket Brass Centerfire Rifle Ammunition
(147)
As Low As (Save Up to 50%)
$12.99
$0.65 - $0.69/Round
See all 7 models
Best Rated
Winchester USA 5.56x45mm NATO 62 grain Green Tip M855 Full Metal Jacket Boat Tail FMJBT Brass Centerfire Rifle Ammunition
Winchester USA 5.56x45mm NATO 62 grain Green Tip M855 Full Metal Jacket Boat Tail FMJBT Brass Centerfire Rifle Ammunition
(132)
As Low As (Save Up to 50%)
$13.99
$0.69 - $0.72/Round
See all 7 models
Magtech 5.56X45 M193 55 Grain Full Metal Jacket Brass Cased Rifle Ammo, 50 Rounds, 556A
Magtech 5.56X45 M193 55 Grain Full Metal Jacket Brass Cased Rifle Ammo, 50 Rounds, 556A
(1)
List: $50.49 (Save 27%)
$36.89
$0.74/Round
Best Rated
Barnes Vor-TxRifle Cartridges, 5.56x45mm NATO, TSX Boat Tail, 62 Grain, 20 - Rounds, *31190
Barnes Vor-TxRifle Cartridges, 5.56x45mm NATO, TSX Boat Tail, 62 Grain, 20 - Rounds, *31190
(10)
List: $57.49 (Save 24%)
$43.89
$2.19/Round
Fort Scott Munitions 5.56 NATO Copper 62 Grain Centerfire Rifle Ammo, 20 Rounds, 556-062-SCV1
Fort Scott Munitions 5.56 NATO Copper 62 Grain Centerfire Rifle Ammo, 20 Rounds, 556-062-SCV1
(2)
List: $47.99 (Save 40%)
$28.99
$1.45/Round
Aguila Ammunition 5.56 NATO 62 Grain Full Metal Jacket Boat Tail, Brass Case, Rifle Ammo, 50 Rounds, 1E556110
Aguila Ammunition 5.56 NATO 62 Grain Full Metal Jacket Boat Tail, Brass Case, Rifle Ammo, 50 Rounds, 1E556110
(1)
List: $32.09 (Save $1.10)
$30.99
$0.62/Round
Barnes Precision MatchRifle Cartridges, 5.56x45mm NATO, Match Burner Open Tip Match Boat Tail, 69 Grain, 20 - Rounds, *30846
Barnes Precision MatchRifle Cartridges, 5.56x45mm NATO, Match Burner Open Tip Match Boat Tail, 69 Grain, 20 - Rounds, *30846
List: $57.49 (Save 22%)
$44.89
$2.24/Round
PMC Ammunition X-Tac Rifle Ammo 5.56 NATO 62 gr Green Tip 1000/ct, 5.56 M855 Case
PMC Ammunition X-Tac Rifle Ammo 5.56 NATO 62 gr Green Tip 1000/ct, 5.56 M855 Case
List: $719.99 (Save 15%)
$608.99
$0.61/Round
Magtech 5.56x45mm Ball M193 - 556ACS
Magtech 5.56x45mm Ball M193 - 556ACS
List: $732.00 (Save 13%)
$635.39
$0.64/Round
PMC Ammunition X-Tac Rifle Ammo 5.56x45mm 55 gr FMJBT 3120 fps 1000/Box, 5.56X Case
PMC Ammunition X-Tac Rifle Ammo 5.56x45mm 55 gr FMJBT 3120 fps 1000/Box, 5.56X Case
List: $689.99 (Save 13%)
$601.69
$0.60/Round
Winchester Lake City 5.56 MM M855 FMJ WIN 62 GR 50 Green Tip 50-20RD Box 1000 rds tot, WM855K Case
Winchester Lake City 5.56 MM M855 FMJ WIN 62 GR 50 Green Tip 50-20RD Box 1000 rds tot, WM855K Case
List: $869.99 (Save 16%)
$732.19
$0.73/Round
Hornady Frontier 5.56mm NATO 68 Grain BTHP Match Brass Cased Rifle Ammo, 500 Rounds, FR310C
Hornady Frontier 5.56mm NATO 68 Grain BTHP Match Brass Cased Rifle Ammo, 500 Rounds, FR310C
List: $500.59 (Save 15%)
$427.69
$0.86/Round
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Ammo Boxes

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Berrys 29682 405 Ammo Box 223 Rem,5.56x45mm NATO 50rd Smoke Lid W/Black Bottom
Berrys 29682 405 Ammo Box 223 Rem,5.56x45mm NATO 50rd Smoke Lid W/Black Bottom
(1)
List: $5.39 (Save 41%)
$3.19
Berrys 11664 005 Ammo Box 223 Rem,5.56x45mm NATO 100rd Smoke Lid W/Black Bottom
Berrys 11664 005 Ammo Box 223 Rem,5.56x45mm NATO 100rd Smoke Lid W/Black Bottom
List: $6.99 (Save 21%)
$5.49
Nanuk 908 Ammo Case, 12.5in, Black/White, Small, 908S-000BK-PA0-AMM01
Nanuk 908 Ammo Case, 12.5in, Black/White, Small, 908S-000BK-PA0-AMM01
List: $99.99 (Save 20%)
$79.95
Berrys 44661 405 Ammo Box 223 Rem,5.56x45mm NATO 50rd Blue Lid W/Black Bottom
Berrys 44661 405 Ammo Box 223 Rem,5.56x45mm NATO 50rd Blue Lid W/Black Bottom
List: $6.49 (Save 51%)
$3.19
MTM Ammo Rack w 4 RS-50-24 Ammo boxes, Dark Earth/Clear Blue, ARRS
MTM Ammo Rack w 4 RS-50-24 Ammo boxes, Dark Earth/Clear Blue, ARRS
(2)
List: $37.97 (Save $3.18)
$34.79
Berrys 86410 005 Ammo Box 223 Rem,5.56x45mm NATO 100rd Blue Lid W/Black Bottom
Berrys 86410 005 Ammo Box 223 Rem,5.56x45mm NATO 100rd Blue Lid W/Black Bottom
List: $6.99 (Save 21%)
$5.49
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CMMG, Inc MK4 RCE Upper Group 5.56mm, 16 in Unavailable & Discontinued Models

List of Unorderable Models

  • CMMG, Inc MK4 RCE Upper Group 5.56mm, 16in, Barrel, Black, 55B5949 , MPN: 55B5949 , UPC: 815835016641 , Code: 2CM-URC-55B5949
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