There really isn’t enough space to have ‘too little’ break angle with a B5 on a Tele, not enough real estate. Pics will help.So I went through the pain of replacing the nut (it was time anyway) and realized it's not the nut. Upon much closer inspection, the strings are definitely hanging on the saddles (again, Mastery 4.1). I guess I didn't really see it before but it's very clear now.
I have a good break angle (not too much, not too little), the nut it cut well, and this darn thing just won't stay in tune. I'm so disappointed, I thought Mastery was the "stuff". Do I have to go to a roller bridge?
Mastery chrome saddles are made for low break angles. At higher angles, they rock/move like any other saddle/bridge combination. The 4.1 saddles move with the string on my B5 Tele, and at first it was like “what’s the point?”, but I stayed with it, and it’s still tuning stable, with full arm movement. This was directly compared to brass and steel barrel, and threaded steel options from Glendale, Gotoh, etc.
Upon first install of the Mastery, I ran out of saddle adjustment range. The guys at Mastery said exactly as above: the saddles work best with low break angles. They recommended I reverse shim the neck so I can lower the saddles, which I did with a piece of card stock. FWIW, I also have a callaham grooved roller. Not saying you need a Callaham or more stuff, but it’s all been working for me with no tuning issues.
What led you to think the nut was completely eliminated as an issue?