No, not normally for this strain is the short answer.
If it is not showing any coloration as yet, it is unlikely to happen at all.
If the temps at night are significantly lower than when your lights are on, then some purple coloring may occur.
But no, Jack Herer is not a purple or red strain.
Also, NEVER grow at 24/0..........all cannabis plants, autos included, NEED a dark period every 24 hour cycle for a correctly functioning metabolism.
A plant with an incorrectly functioning metabolism will never reach its full potential.
There are certain metabolic processes a plant does during the night period that it can not do when the lights are on, and without doing these night time processes, your plants will be functioning incorrectly.
18/6 is optimal.