Mallard1123-
More than three years ago I wrote some long posts about selection of twist rate in this thread:
BARREL LENGTH AND TWIST RATES DISCUSSIONI haven't gotten any smarter or learned a whole lot since then on the subject, so have a look at some old stuff. Come back with any questions and I'll try to answer them.
One of my bolt rifles has a 1-in-16" twist, the other 1-in-24". The former was not a particular selection; the barrel cam with that twist. I did select the 1-in-24" twist fore the barrel on my 450B heavy rest rifle. It was what the factory AR barrels at the time were using, and I wanted to be sure any data I generated would be useful.
--Bob