I feel strongly that the 250gr best describes the Whelen in the majority of cases. Although the 225gr is, in all likelihood, the most commonly used bullet weight when it comes to handloading.
In my Whelen, I have come to prefer the Lyman 358009, 282gr GC hard cast from W/W, at a very modest 2050fps. My rifle has a 1:12 twist in a 26.5" Douglas #3 bbl, and of all the guns I now own and have owned over the years, this particular rifle / caliber combination is my favorite... by far.
No matter what your choice of bullet weight, with 200gr and over, the Whelen seems to be able to get the job done, and done right.
Russ...