Shooting to disarm: I remember discussing this one on the Mythbusters Fan Club Forum, so I already have some idea of the physics involved. What I figured is that it's a matter of action and reaction -- if firing the gun doesn't knock it out of your hand, then the impact of the bullet on the other guy's gun shouldn't knock it out of their hand either.
So how come they had success with knocking the gun out here? Well, I'm not happy with Jamie's gripping rig. It's too passive; there's no muscle response involved. I would've rather seen something mechanical that exerted an active grip, or at least something spring-loaded to generate pressure. Now, maybe if someone were holding the gun loosely and taken by surprise, it might knock the gun out of their hand before they could compensate and hold onto it. But like I said, if you can hold on during the firing recoil, they should be able to hold on too.
Someone else on the message board pointed out that the bullet takes a brief time to leave the barrel, which would spread out the delivery of the force, and that the force of impact might be delivered more in one burst and thus have more effect. That might be true, given the result of hitting Adam's target-with-handle thingy with the bat, and the similar forces involved. Still, I wonder how much of it is a matter of the direction of the force. A gun handle is designed to cope with the recoil force pushing backward against your wrist and arm, but in the "draw" and "hostage" positions, the force was perpendicular to that. So maybe it's something that can only work if the other guy's gun isn't pointing right at you.
And indeed Adam and Jamie's final results with the remote-control, double-handle gun bear that out. As well as supporting what I suspected, that it's more a matter of surprise than force. You can hold on, but only if your startle reflex doesn't cost you your grip. That confirms my initial thinking about the action and reaction.
So why was it so much worse with the baseball bat? Perhaps because the force was delivered more gradually, more continuously.
Of course, that still leaves the shrapnel, a factor movies and TV routinely ignore. That damage looked pretty devastating. Now, what I'd like to see tested is: what would happen if you used silver bullets? After all, the disarming shot was the Lone Ranger's trademark.
Speed bus jump: The small-scale result went pretty much as I expected, except, like Jessi, I didn't expect the bus to even get as far as it did. The bit about calculating the correction for unscaled gravity (once the plan to test it on the Moon fell through) was interesting.
Is it me, or is the junior team doing the more elaborate myths lately? Jessi certainly got to show her stuff as a builder this week, constructing the miniature freeway section and contributing to the construction of the big ramp from the steel container. (That's just so wild, cutting one of those big things in half on a diagonal and making a ramp out of it.) Although it still seems she's being treated as a junior member of the junior team, not getting as much screen time as the guys.
And Grant seems to be better than Adam and Jamie at rigging remote-controlled vehicles that actually shut down when you tell them to. Maybe just because he's learned from their experience. Or maybe it's because radio control is his particular specialty (as he alluded to, he's one of ILM's three official R2-D2 operators).
At least, it seemed that way for a while. It wouldn't be a Mythbusters radio-controlled-vehicle experiment if they didn't crash through the fences at Alameda at least once. The thing is, they made it harder for themselves than it needed to be. Why didn't they just reuse the tow method that was used for the semi trucks in the Compact Compact myth? That would ensure that the bus stayed on target, if a cable was towing it there. And I recall one myth where they set up a tow rig with some kind of self-correcting axle in front that ensured the vehicle would stay on a straight course. No need for all of Grant's wobbly steering. Heck, the least they could've done was to have Grant watch the video feed from inside the bus for steering purposes. From what he said, it sounded like he was just eyeballing it from behind.
and how Jamie modified the concept to make it work. Well tested, as Jamie and Adam usually are, though I'd say the final result was more "plausible" than it was "busted." I'd also quibble that the fake handle didn't have the trigger or the gaurd there, the shock of that hitting your hand could hurt enough to cause a drop reaction.
