I have access to a lot of research on the English Dowleys. (We thought once they might be Irish too, but they all seem to be Londoners instead!)
At the Family Records Centre (FRC) in London, I noted the following last year:
From "Army births and baptisms" index - George H. DOWLEY born Bangalore, India 1880 – father is listed as being in the Royal Artillery.
You could get more details by getting a copy of the birth certificate via the FRC.
The Public Record Office in Kew, London, should have a copy of the military records of George H. DOWLEY's father.
Knowing you are looking for a member of the Royal Artillery will save time. If the soldier died in service, the records were not kept. Hopefully he survived and so will his records! They give a physical description, trade, place of birth and place of enlistment.
Other records in which he might appear would be muster rolls and medal rolls.
Do you think this George H. DOWLEY might be your grandfather? The dates would seem to be about right.
You might be looking for an Arthur DOWLEY, then, born about 1850s perhaps?