In general how many missiles\grenades should you get per requisition? I think it should be usually 3 grenades as standard issue frag and krak grenades come in 3 round allotments. Anything confirm\deny this?

BTW I know that a vortex grenade is a single issue item if it's even given out.

Errata, p.9:

"Character receive unlimited amount of standard ammunition for their standard issue weapons and their Signature Wargear weapons per Mission, and do not need to keep track of the remaining standard ammunition or its weight. At the GM’s discretion, the characters may run out of standard ammunition in situations where resupply is not available. As a general rule, the GM may opt to use the “rule of three,” meaning that each Space Marine has three reloads for each ranged weapon unless otherwise noted."

Wow, talk about fast service!