Hodgdon's data lists 44.0gr as a max load and is the fastest listed load @ 3,460fps. (from Lee #2, pg290).
I would suggest you use the Hornady 75gr v-max, or the Hornady 75gr HP.
I've not loaded these in the .250Savage, but have the .257Roberts. I would These have a higher ballistic coefficient than the Speer or Sierra, also start at 40.0gr and work up. No data is given on what cases, primers, ect is listed.
I used Federal #210's, and Winchester cases. I easily reached the Hodgdon listed max, which are non-+p for the .257Robt.
I have used H414 and the 75gr HP in the .257Roberts. It was a good load, but H380 gave better accuracy with essentially the same velocities.
Accuracy was exceptional and I even killed several deer one night on a deer control permit. I made the longest shot I've ever made on a deer and was a bang-flop at a measured 378yds. Bullet broke the deers back just behind the shoulder and exited with a 1" diameter hole. Just about perfect, give the reduced velocity at the extended range.
But, FWIW the Nosler 85gr Ballistic Tip is a better choice for any reasonable use of the .250 except for larger deer.
Let us know how it works !!!!