I have collected a bunch of twist calculators. Some use only twist and bullet length, some use velocity as well.
For the types of rifles I shoot, it is generally accepted that the Greenhill constant of 150 needs to be downsized to about 130 or 125. I have found that 125 seem to do the best job of predicting the ragged edge of stability in slower BPCR rifles with lead bullets.
So using the numbers you supply and guessing a velocity of 1900 fps, I get
Greenhill (150) -> 0.81" for max bullet length
Greenhill (130) -> 0.70"
Greenhill (125) -> 0.675"
Carr -> 0.70"
Crawley -> 0.83"
Lilja -> 1.035"
Charley Dell -> 0.83"
Obviously, Lilja sticks out like a sore thumb for being different from the others, but I suspect that is because it is probably developed for very fast, very point, boattailed, jacketed bullets.
If it was me, I would look at these numbers and figure I want to be under 0.8" long. Probably around 0.75 would suffice for me. If I was planning to shoot very far (>500 m), I would go shorter yet.
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