[catman67]

That “grenade launcher” under the barrel could be a 37mm flare launcher, which is still legal. Mounted too far forward in my opinion. Also, looking at the mag, it appears that this is a SCAR-17 (.308).

[rdcbn]

Rifle looks like a SCAR 17, but it does not look quite right for a real FN made SCAR 17

Could be an airsoft type knock off

A SCAR 17 with flare launcher and scope is about a $6000.00 set up