Strip husks and silks from 6 ears corn (7 to 8 in.).
Prepare barbecue for direct heat.
If using charcoal briquets, cover firegrate with a single, solid layer of ignited coals; let them burn down to desired heat. Set grill in place and measure heat.
If using a gas barbecue, turn all burners to high and close lid for 10 minutes. Adjust burners to desired heat. Set grill in place and measure heat.
When grill is medium-hot (you can hold your hand at grill level only 3 to 4 seconds) lay corn on barbecue and turn ears as needed until hot and speckled with brown, 10 to 12 minutes.
Rub corn with lime wedges and sprinkle with salt to taste.