Calibers Compatible With Standard AR-15 5.56mm Lower

One of the great strengths of the AR platform is its flexibility.  There are multitudes of ways to outfit your rifle.  Not least of which is the choice of ammunition .  With the simple change of upper receiver, many different types of ammunition can be shot with your standard AR-15 .223/5.56mm lower receiver.  This means that your trigger stays the same, but the caliber of ammunition fired through the gun can change.  Below are uppers available for a standard lower.

6 x 45
7 x 40
357 Mag Rimless
300 Whisper / .300Fireball / 300-.221
6.5 x 40
.30 Coyote (30 x 45)
.17 Remington
.17 Mach IV
.20 Tactical
.19 Calhoun
5.7 FN
.204 Ruger
6.8 SPC
30 HRT
338 Spectre
10 mm Mag
35/40
219 WASP-C
7.62 x 40
5.45×39
7.62 x 39
.338 x 39
6 PPC
6.5 Grendel / 6.5 AR / 6.5 PPC Improved
22 PPC
7 sCAR
30 Carbine
5.45×39 / .21 Ghengis
7 BR
6.5 BR
300 Sabre
8mm
458 SOCOM
44 Mag
440 CorBon
44 AMP
.475 Tremor
50AE
499LW
50 Beowulf
.50 BMG
.50 Blackpowder
9mm
45ACP
32ACP
22 LR
17 HV
10mm
7.62×25
224 BoZ
7.62×24
9×23
.357 Sig
.357 Auto
40S&W
223 WSSM
243 WSSM

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