Redirecting the homepage URL from http to https

Redirecting the homepage URL from http to https happens as a 307 Redirect on some well built sites (google.com and moz.com for example), but as a 301 Redirect on others (searchenginejournal.com for example). Best way to see it is type in both the www and non-www versions and view the loading sequence in the Chrome Developor Tool`s network tab.

Is this OK? Does the Google search engine treat both a 301 or 307 flip from http to https as equivalent for ranking purposes?

Any code examples or article links on how to always make the http to https switch a 301 Redirect, like SearchEngineJournal.com does??