The FN Herstal SCAR-L assault rifle fires 5.56x45mm rounds from M16 clips..
The FN Herstal SCAR-H (heavy) fires 7.62x51mm NATO ammunition.

Usage in real life:

• The SCAR-L is chosen to replace the M4A1 carabine, the Mk18 CQBR and Mk12 SPR.
• The SCAR-H will replace the M14 and Mk11 sniper rifles.