S.C. Code Ann. § 24-13-440
It is unlawful for an inmate of a state correctional facility, city or county jail, or public works of a county to carry on his person a dirk, slingshot, metal knuckles, razor, firearm, or any other deadly weapon, homemade or otherwise, which usually is used for the infliction of personal injury upon another person, or to wilfully conceal any weapon within any Department of Corrections facility or other place of confinement.
A person violating this section is guilty of a felony and, upon conviction, must be imprisoned not more than ten years. A sentence imposed under this section must be served consecutively to any other sentence the inmate is serving.