Some of you may have heard of this or run across it: Up to 3 missiles may be dodged, but any salvo of 4 or more missiles hits automatically.
This has become known as the "Airwolf missile rule" after the '80's adventure show Airwolf. In one episode, much is made of a weapons system that fired 4 missiles at once, because "nobody could dodge 4 missiles." Of course, the Airwolf helicopter winds up dodging all four missiles. So why can't you?
The answer: Playability. Since each missile requires an attack roll, then a dodge roll, then a damage roll, a large salvo of missiles has the astonishing ability to bog down play. So while this rule feels like a wallbanger (and is), it does have a reason to exist.
Lesson learned: BTR will need to have a mature and playable set of autofire rules for quickly and easily resolving multiple-projectile attacks.