Denton, the rifle I often use in 7x57, I get 2800 from a 20" bbl. My best hunting buddy has a 24" bbl on his, and he gets 2900. Both 140 grain.
I load for both, and use Hodgdon 414. 4350 would be a close second choice. I tried both in both rifles. the 414 seemed to shoot groups just as tight or tighter as I got close to max, the 4350 seemed to open up a little. FWIW
2 rifles is a clue, but far from a scientific test sample.
BTW, my buddy's rifle that shoots 140's at 2900 is a Whitworth Mauser- made in Zastava, I believe.