Are your velocities higher than maximal book velocities for that cartridge with that weight bullet? That's the first clue.
But, to provide some pushback to "you're going to blow yourself up!" - first I will say, you don't want to go kaboom! But you're not going to go kaboom unless you're a real moron if you're using the usual powders for a cartridge/bullet combination. You will have obvious pressure signs (stuck case, can't open bolt, etc) long before you go kaboom. Look at Orkan's video of H110 filled to overflow in a 338 LM case with a DT rifle. No kaboom, just an irreparably destroyed bolt. Kabooms are more often caused by squib loads, or that moron from KY with the 50 BMG shooting sabots with a brake. There is no substitute for common sense when shooting.
Which takes us back to most of the comments - start comfortably below stuck case, heavy bolt lift, ejector marks, blown pockets, stop when you get there, and then back off significantly, so that differences in case volume, temperature, powder humidity, seating depth, etc, have enough "buffer room" to keep you safe. I think it's folly to be running a "max load" under pretty much any conditions, because when conditions change, so does your safety buffer.