Wouldn't it be cool if you could have a mounted gun on a vehicle that when fired, left holes in whatever is being shot at? I have no idea why I want this, but I do lol.
It would be cool, but it'd require far more high-fidelity JBeam structures to allow for mesh tearing. At least three times what we have now to simulate a bullethole the size of a large-caliber round, eight to twelve times to simulate small arms or make high-caliber holes look natural. Needless to say, that's not going to happen within the next decade or so. As it stands, the only projectile that is natural to the game is the cannonball, and even it is absurdly large and heavy.
It may take a decade... on this software... Maybe some new software will come out that can support more advanced simulations using less power? hey, if they could sometimes hit 60fps on GTA IV on consoles, then there must software that will come in a year or two that will let us do advanced simulations like that but with the tech we have today, not going to happen.
Are heat-seeking rockets close enough? --but seriously, It may be possible to at least do some damage with a small projectile in 100x slow motion (imported from here)
Shooting out tires and engine blocks could be a shitload of fun. If water can kill an engine so could a bullet?
Hence why naval operations combatting smugglers and piracy carry .50 cal sniper rifles with red dot or other short range type scopes. They use them for destroying outboard motors on boats. .338 lapua magnum has been said to be capable of dealing catastrophic engine damage to a humvee from 500 yards or more.