Hi John
In 1837 the 27th Regiment was in the Cape Colony. They would have left a depot behind in the UK to carry on recruiting. This was a time when there were very few barracks so the depot would have moved around a lot. They also thought it desirable to keep men moving, so they didn't go soft. In the 1820s when the battalion was home, it moved around such places as Limerick, Buttevant, Fermoy, Dublin and usually moved on within six months. So it is not a surprise if a birth for the 27th Foot was recorded in Limerick.
For the other dates the battalion was in India from 1854 to 1868. At the end of 1860 the depot was in Fermoy.
Ken