Re: NEW 300 WSM whats the max load on R17?
According to Richard Mann (writer, Handloader magazine), the traditional high pressure indicators (i.e., crater primers, ejector marks, stickly bolt lift, etc.) are even less reliable when using Reloader 17 - they can be absent even after safe pressures have been greatly exceeded.
He suggests finding IMR 4350 data for the bullet you want to use, and use a RL17 starting load that is 5% below the MIN starting load for the IMR4350 data. Increase charge wieght until you see the traditional high-pressure indicators AND/OR when you are 50-100 fps faster than the max velocity listed the bullet you are using. The article is located on the Loaddata.com site (you will need to purchase access to read the article).
I tried this suggestion and found that it was in close agreement with Quickload predictions for the bullet I am developing for (i.e., 300 WSM, 180 g TTSX). By the way, 61.0g is the max charge weight that Quickload predicted for a 180 g TTSX.