Clean old paint from interior stonework

[Draughtsman]

The stonework was reclaimed/repurposed from a much earlier building. Where there is paint it's chalky creamy and turns rust red if I try to wash it off with water. Will paintstripper gel take it off and wash down without permanently staining the stonework? Generally, I'd like to clean the stone surface using minimal elbow grease.
Thank you.

 

[Harry Bloomfield]

Sand blast?

 

[Draughtsman]

Inside the house? Maybe not.

 

[Wayners]

Try C-TEC PEEL TEC paint remover.

Test area. Supposed to not damage surface