You are back from a sulfur run with roughly a C4's worth in the box, and someone wants explo instead. Do the sum first. A full stack comes to 3,200 sulfur against 2,200 for one C4, so stacks only make sense when the targets are soft and there are many of them.
Like explosives, the recipe takes raw sulfur on top of the gun powder, so keep some out of the powder queue. The blueprint costs half the scrap of the explosives one and sits behind the same Level 3 bench. If scrap is tight, learn explosives first: they lead to C4 and rockets, while explo only ever fills a rifle.
Craft it in small batches right before the raid. Rounds sitting in a box are sulfur that can no longer become a rocket, and on stone the rocket is the better use of it anyway. Ordinary 5.56 is what you stockpile.
Questions
Explosive 5.56 Rifle Ammo ×10: how many resources?
Sulfur ×250, Charcoal ×300, Metal Fragments ×50.
Which workbench does Explosive 5.56 Rifle Ammo need?
Workbench level 3.
How long does Explosive 5.56 Rifle Ammo take to craft?
7 s for one, every step included.
How much scrap does researching Explosive 5.56 Rifle Ammo take?