I've been researching loads for modern actions for the 7x57. Most printed data is extremely conservative because of the older 98 actions, they like to keep PSI at 45,000. I've got a No. 1 in 7x57 and decided to try a ladder test using Reloader 17. Reloader 17 runs similar to IMR4350 and the maximum load printed by Speer using 175 grain bullet is 45 grains of IMR4350. I'm using the 168 AccuBond but there was no load data for the 168 grain bullet. One advantage is I was able to take advantage of the actions long throat. The published Maximum OAL is 3.065, I can use a maximum OAL of 3.280 which leaves additional room in the cartridge. Started the test off at 44 grains and gradually worked my way up. The difficult part was allowing extra time for the barrel to cool, I'm in Arizona and it's going to be over 100 again today. I started at 7:00am to take advantage of the cool morning. I was also sighting in three other rifles so I switched back and forth between them. Long story short I quit at 47.5 grains. This load is accurate in my rifle and I felt like I was reaching the safe maximum for my particular action. There were no signs of high or over pressure, the primer corners were still nicely rounded, not flat and the action opened and closed without incident. I just felt the 2 and a half grains over the printed maximum was enough. I'd brought a few cartridges loaded with 48 grains but something inside me said enough was enough. Later this week after I do some more reloading I'll take my new Magneto Speed Chronograph out and see what velocities I'm running at using 47.5 grains of reloader 17. Based upon review of other weight bullets and loads I should be somewhere between 2,750 and 2,850fps. Quite a difference from the 2,433fps, the stated velocity using 45 grains of IMR4350. Four hundred feet per second makes a considerable distance when calculating a maximum point of impact.