You don't show a location, which would be helpful to answer your question.
You can calculate your stability free online using the Miller Stability calculator at JBM.
JBM - Calculations - Stability
If your handle indicates you are in Wyoming, then don't use sea level. 29.92 is standard at sea level, but at 5000 altitude as in Colorado or Wyoming, the station pressure is 24.92 on a standard day. That bullet is 1.365" in length. Using 3000 fps as a guess, 8 twist, then...
at sea level, 29.92, 59F, the stability is 1.241 (too low)
at sea level, 29.92, 0F in winter worst case, stability is 1.100 (too low)
at 5000 ft ASL, 24.92, 59F, the stability is 1.490 (good to go)
at 5000 ft ASL, 24.92, 0F in winter worst case, the stability is 1.321 (marginal, probably OK)
Berger's advice on 1 in 7 twist applies to those at or near sea level, and not in the High Plains at 5000 ft ASL. They are giving advice for worst case (seal level in the winter).