I started a reloading project which is not yet complete using RL-17. Fed 215 primers, RP brass and Hornady 139 BTSP bullets. I worked up the loads to shoot in my Rem 700 in 7mm SAUM. Here are some of my results.
55 grains RL-17 2900 ft/sec
56 grains 2947 ft/sec
57 grains 3008 ft/sec
58 grains 3087 ft/sec Three shot group ES of 17 ft/sec. All these loads were three shots only and the velocity is an average for the three shots.
I have loaded a few more rounds at 58.5 and 59.0 grains but I have not shot them yet.
So, it looks as if you could start at 55 grains and work up like I did and you could find a good load with this powder.
I know that the burn rate of RL-17 is close to IMR-4350 and Hodgdon gives a max load of 61.2 grains for 3174 ft/sec. with a 140 grains Nolser BT, so I think I can move close to 60.0 grains without difficulty. I plan to do this sometime in the near future. I will be watching for signs of pressure as I move up at .5 grains steps.