Well, the Bradley (L x W x H 6,55 m x 3,28 m x 3,38) is bigger than the 251 (5,8 m x 2,1 m x 1,75 m).
Is the size ratio between the two models realistic? I don't know.
To be sure, take a sliding gauge, measure the models, multiply the measured values by 144 and compare the results with the original ...