I worked up to 45.0 grains a few years ago with Varget and the 120 TTSX. Accuracy was superb and velocity averaged 3025 out of my 22" barrel. Primers were fine, no sticky bolt lift, etc.

i don't remember the source, but I think it was online data from Barnes. I'm not one to push the envelope, so there was some trusted data somewhere that supported 45 grains of Varget.