England Births & Christenings have only two listings for Henry Ransom around 1825. One was in Hastings, but as census records are available post 1841, this Henry can be discounted.
The second was christened 31July 1825 in Brighton, East Sussex, the son of Henry Ransom & spouse Mary. I believe Henry (sr) married Mary Hoite in Hastings, St Clements on 8 June 1823. Likely candidates for Henry & Mary appear in the 1841 census living in the district of Beckley.
There is no certainty that your great grandfather was this Henry Ransom christened in Brighton, as Brighton & Catsfield are some distance apart. Beckley & Catsfield are much closer.