Sturgeon was a great Calvinist preacher. He didn’t believe in double predestination. Calvin also believes in common grace.
Calvinists who believe in double predestination are rightfully called hyper-Calvinists. IOW, they out Calvin Calvin.
They do not out Calvin Calvin. They believe exactly what Calvin taught - Hyper-Calvinists are the real Calvinists. Everyone else is misusing the label.