Banned at the (very) CQB Depot, which seems surprising.
But it's a marshalling / monitoring issue on a busy site with a high player turnover, that acknowledges the reality of airsofters' capacity for not listening, or caring, or thinking that rules apply to them.
If they allowed grenade launchers, then even if they said "MOSCARTs only" half a dozen times at the briefing, I guarantee some joker will load up a 40-Mike, or will point blank someone with a TAG round, or put 6 BBs into a shell gassed up to eject 120 and then say "Whaaaaat? It's a MOSCART!"
They
shouldn't, but they will. Bloody airsofters, ruining airsoft for airsofters.