Here's the deal, the team is going into a hive ship. I've got a large party, so in order to give it a semblance of challenge, I plan to make endless hordes of Xenos a part of the scenery for a good chunk of the mission.
Shortly after they make entry, the hormaugants start flooding in. On the one hand, I don't want to be roll-playing the entire night. On the other, I want to be fair and hold them accountable for their requisition usage and tactical decision making. So I basically took their equipment and ammunition choices and averaged their horde damage as a fixed value.
Provided the team is completely exposed, they must put out at least 120 damage to horde magnitude per round in order to keep the enemy at bay. They need additional damage (1:1 damage/meter) to make any forward progress. So 30 damage per 90 degrees of exposure. They'll want at least 125 damage/round to be able to move fast enough to keep up with the mission time line.
They'll need to keep this up for roughly 1 hour, 29 minutes of in-game time.
The way I see it, the ammunition they bring with them is the limiting factor. The guy running the heavy bolter is going to burn a magazine (6.8kg) every 6 combat rounds. But he's using a backpack supply (40kg), which will run for 25 combat rounds. Looking at 1068 combat rounds, he'll need roughly 43 backpacks or 178 detachable box magazines to keep it rocking for the whole show.
I do not see that as being a feasible quantity of ammunition to carry around on a boarding mission.
Likewise, let's say they pool their requisition and purchase ammo to feed it. With the points they have left, they could afford 305 box mags for the heavy bolter, provided NA requisition cost = 0, so +5 for a heavy bolter mag = 5 requisition per magazine. They've got the points, but I just cannot rationalize how it could be hauled around.
We've got some house rules for carrying capacities on extra munitions, but nothing to really cover something quite like this. With the average SB+TB total of 16, these guys are able to physically heft this much material with ease. But no matter their strength, the size and bulk of the items in question make it an impossibility in my estimation.
Typically, I limit them to 3 standard mags and as much special requisition ammo as they can afford. But how would a single character strap 10 heavy bolter box magazines to himself?
Just these kinds of glaring logistical issues with regard to long duration, high-intensity combat missions. Any solutions?