Some people say you don't get the same bang for your buck at McDonald's these days . . . but THIS is a pretty big bang.

McDonald's has unveiled their new "Big Arch Burger," which will be arriving throughout the U.S. next Tuesday . . . but only for a limited time.

They say this is their "biggest and boldest burger yet." It features two quarter-pound beef patties . . . three slices of white cheddar cheese . . . crispy onions . . . slivered raw onions . . . lettuce . . . and pickles. 

It comes with "Big Arch Sauce," which is "a perfect balance of mustard, pickle, and sweet tomato flavors."  As well as a toasted sesame and poppy seed-coated bun.  And the burger is "big" in more ways than one . . .

The Big Arch weighs in at 1,057 calories, which is more than three times the calorie count of a McDonald's cheeseburger at 303 calories, and about double the count of a Big Mac at 509 calories.  There's no price info, but one estimate suggests it'll run you around $12 or $15 for a meal.