Range War Westerns #4 is a reprint of Badman Western Library #4, which may be a reprint of a previous Page Publications issue.
The cover is from the splash page of the Wyatt Earp story "Vengeance of the Apaches!"
Issue #3 of the Range War Westerns series featured a Keith Chatto cover, and I expect the first two issues did too.
This issue appears to be a belated addition to the series . The increased cover price and the el cheapo cover suggest this was a quick and crudely contrived publication, and tacked on to the existing series as an afterthought.