I don't have access to NRA annual reports, and am not sure that they would necessarily feature Volunteer competitions in general. Many of these events are however covered in the press. I have checked The Times for the period and can't find anything. The local record office/library will most likely have copies of regional newspapers which might be a good source for information.
 
David

The answer to your query is probably in the pages of the Volunteer Services Gazette.  It was a weekly publication and carries this sort of information. Complete runs of this Gazette can be found at the Newspaper archives at Colindale, in the War Office Library (not available) and in the library of the National Rifle Association at Bisley.  As far as I know there are no other runs anywhere.
 
A letter setting out all the information you have should be sent to Mr Ted Molyneux, Curator, Museum of the National Rifle Association, Bisley Camp, Brookwood, Surrey GU24 0PB.  If you ask him to be so kind as to check the VSG for a few issues immediately following the event, he may well be able to find it for you.  You might also ask him to check the NRA Annual Report for 1863 as it might be in that.  The earliest NRA Annual Reports (1860/61) did carry such information but the increasingly sheer volume of such reports soon caused the NRA to stop adding them.  I do not have the 1863 Report so cannot say from here and I normally only work at the Museum in July for the Imperial Meeting.
 
Bill Curtis (Asst. Museum Curator, NRA)