I have been running RL17 in my son's 7x57 with 140 AB's. Speeds are real good in the 2900 range and accuracy is looking pretty decent since I haven't touched the bullet yet.
RL19 was a little slow for the 140's, but really accurate and still running 2750. Haven't tried any of the 4350's, but they will come if RL17 doesn't pan out.
Congrats on a great rifle!
