Book velocity, adjusting for barrel length and such, is my general guide. No free lunch exists.
Like others, I’ve also been bitten by stout loads that were worked up in cooler temps. A strong load of RL17 in a 6.5x47L did not agree with 90 degree days. Ditto for 335 and the 223AI, as others have mentioned. Only primers I remember popping.
Sticking with book speeds, testing in warm months, and trying to lean toward heat-stable powders for “fun” guns has helped.
