This is something that has begun to rear it's ugly head once again ont' t'internets. It makes me sad, because it's a crock of shit. [That's why the pic of Katy Perry instead of a boring old Boltgun. Well, that and because I add the picture at the end of the process, and so dear Katy became more relevant to the...ah, just keep reading, you'll get it. Not even the best pic of her if I'm honest, but it'll do. /digression]
No, really, it's a complete and utter fabrication. It's bullshit, plain and simple. Has anyone ever tried actually doing it?
Let's run through it. Bolters are (typically) carried by Marines, so they will hit 2/3 of the time. They will successfully score a Glancing hit on AV10 1/6 of the time - which means you require 6 hits to average a single Glance, and as you can see that requires 9 shots to average even a chance to inflict damage.
But wait, there's more.
As we all know, Glancing hits suffer a -2 penalty to the chart, meaning that the most damaging result on a non Open Topped vehicle it is possible to get with a Bolter is an Immobilised result. Now, while sometimes that can destroy a target outright, ie if it moved Flat Out in the preceding Movement Phase [side issue, this explains the FAQ wording, as without this a Flat Out Scouting Vendetta destroyed by a player going first against it would not be Wrecked...] this is a lot less likely than not Wrecking the target (and, of course, the Flat Out targets will have Cover Saves.)
Let's assume instead that the target did not move Flat Out, has 2 weapons (what self-respecting vehicle doesn't?) and has no Cover (generous to Bolters on that last, but even so...)
So, we need to generate a grand total of 4 Immobilised/Weapon Destroyed results in order to Wreck the target and generate that Kill Point...and prove the assertion and Internet Wisdom correct.
Since that's a result that can only be generated by rolling a 5 or a 6 on the Chart, that's a 1/3 chance, which means 1/18 Bolter HITS will be getting that result. Since we need 4 of these results, that's 4 times as unlikely - a 1/72 chance. Since only 2/3 of our shots hit, that means that, unless my maths is way off base, we require an average of 108 Bolter shots to statistically be killing the target.
Not only is it literally impossible for a single unit to provide that weight of fire, I don't think there is an AV10 vehicle large enough that you can fit 94 Space Marines within 12" of it, or indeed whatever combination is logistically possible, even if you can fit them into an army list, and ignore the other improbabilities of the situation.
Yes, Bolters CAN kill Vehicles - but the chance of them doing so is so slim that it is statistically irrelevant. You may as well discuss the odds of me pulling Katy Perry, because they're similar. *
* - Disclaimer: If I *actually* pull Ms Perry, that doesn't mean Bolters destroy vehicles enough to bother discussing. In fact, I'd go so far as to say that if it did happen, Bolters would be a much less interesting topic of conversation.