Always worked well for me with K-64. 1/250th@f8 or equivalent.
Sure, it works great out on the lawn at 2:00pm. What do you do under difficult conditions? Meter. At no time over the past 40 years have I been wealthy enough that I could afford not to meter.
With B&W, I use kind of a bastard zone system which doesn't leave room for error, either.
Well of course, it's "Sunny 16". That's when I use it-when it's sunny. No need to meter when I know the the conditions. On a very bright inland SoCal spring or fall day I close down 1/3 or 1/4 stop. On a smoggy summer day I seldom add exposure, because I usually want it to look the way it really does- a little dimmer and yellowish. We hardly ever have those really smoggy days we used to have, though.
What do you do under difficult conditions? Meter.
I meter or rely on experience, depending on the details of the situation.
I do use a digital device in my photographic pursuits when necessary.
When someone rags on me for using film, I use a middle digit, upraised.
I miss those little fold up sheets that used to come in the film boxes.
Sunny-16 rules. Last summer I made a mistake of trusting my in-camera meter and a whole roll was drastically over exposed due to a dying meter battery.
I should remember the habit of sanity checking the metered settings with Sunny-16 observations.
Sunny 16 has saved me here, too. I always eyeball and compare my in-head exposure estimate with the one on the meter. If nothing else, it's good mental excersise