To get ahead as a Security Manager, you need a college degree. You also need to keep up with security policies from DSS and other agencies that have an effect on your company contracts.
From contractor to contractor pay does vary. I believe smaller companies pay more than bigger companies because of (job security, retention).
It helps to know about physical security, access control systems and personnel security.
I am a 30 year old Security Manager/FSO and I make 75k a year with 4 years of security experience on the contractor side. Also, have 8 years IT/Security military experience.