S.C. Code § 25-1-2735
If an accused makes an irregular pleading, or after a plea of guilty sets up matter inconsistent with the plea, or if it appears that he has entered the plea of guilty improvidently or through lack of understanding of its meaning and effect, or if he fails or refuses to plead, a plea of not guilty must be entered in the record, and the court shall proceed as though he had pleaded not guilty.
With respect to any charge or specification to which a plea of guilty has been made by the accused and accepted by the military judge, or by a court-martial without a military judge, a finding of guilty of the charge or specification may be entered immediately without vote. This finding shall constitute the finding of the court even though the plea of guilty is withdrawn prior to the announcement of the sentence.
S.C. Code § 25-1-2735