I was mostly reacting at first not to the exact charge the guy in quextion was using, but his muzzle velocity, close to 2700 fps with the Nosler Partition, which indicates WAY too warm a load for the .35 Whelen.
The Partition tends to create higher pressures than the Hornady Interlock of the same caliber and weight, mostly because of longer bearing surface but also because the Partition tends to "bump up" then the rear core is booted by expanding powder.
So I looked up Nosler's own data for the 250 Rl-15 in the .35 Whelen and found 53.0 grains as maximum, for a muzzle velocity of over 2500 fps. This is when I suggested the guy's load might be a little hot. It might not be with a Hornady Interlock.
