G string up to c?

Hi all, wondering if I could tune a g string up to c an octave up from the usual c?

Hmm, I would typically think not. Using an 'a' string might have a better chance. It is certainly possible to have the 1st string be a 'c' note but you may need to get an entirely different string depending on the scale. For example, soprano scale tuned to Eb is a thing, and that would have a high 'c' string

Normally, you would only take a string up two half steps, occasionally three, so you would be risking breaking it, to my mind.

As Jim Hanks said, tuning an 'a' string up to 'c' should be possible, I would say especially on a soprano, and if the strings are designed for tuning ADF#B. For that I can vouch for either Pyramid or Harley Benton soprano strings, which I often tune up to Bb,Eb,G,C on one of my sopranos.