tire width and rim size

[67ragtp]

Question for you guys, If an 18/35/275 tire is mounted on a 10 inch wide wheel, will the overall width(side wall to side wall) of the tire be smaller mounted on a 9.5 inch wheel? The tire is a toyo r888.Im told that a 275 tire has a rim mounting range of 9 to 10 inches.
My gut feel is that it will not change a full 1/2 inch and possibly bulge on the smaller wheel.
If anyone has dropped rim sizes or has some info, Im running out of ideas. Other than spending rediculious amounts of money for new wheels.

Thanks Rich