O.K now I feel really dense...
What are SWB, RSM (WO1), 'Wind Up' jacket, collar dogs ?
I had to compress the picture I thought, to get within the 500KB allowance. Will have another go with an original size.
Grandad was born in 1998, so if the photo was taken around 1918 it would make him 20.
I know he married in 1924 and doesn't seem to wearing a wedding band.
Odd looking bunch though really. Such a mix of hairstyles, from comb overs to mohicans 
Oops sorry...
SWB Silver War (Wound) Badge
RSM Regimental Sergeant Major
WO1 Warrant Officer Class 1...Rank of RSM
Wind Up jkt....Snipers in early WW1 picked out officers easily because of the rank was patent when worn on the wrist. Officers became "widy" of got the "wind up" and thus the rank was moved to the epaulette.
Collar dogs are the Regt badges worn on the collar
As I say, I reckon post war and around 1920, although the lack of medal ribbons on the officer would indicate 1918 early 1919...Unless he had earned none! Unusual but not unthinkable...
