Verify your thread diameter and pitch, and you can refer to this chart
http://www.mgtd.ca/screw%20torque.htm
As the statement says, those values are inch pounds. There’s a handy conversion chart on the same page if you need the foot-pound values.
Go with the column ID’d as "Silicon Bronze".
Note that the torque values for silicon bronze are slightly lower or higher than many of the values for mild or low-carbon steel, but the upshot of it is that, to me at least, they are comparable.
Hope this helps.
Best,
PM T2
He's livin' in his own private Idaho..... I hope to go out quietly in my sleep, like my grand-dad did..... and not screaming, like the passengers in his car...