Help to identify Grantham training camp soldiers please

[Penmon]

My grandfather, 57439 P.T.E.  M.G.C. OWEN JOHN ROBERTS (Machine Gun Corps) is pictured below with pals at Grantham on duckboards, by a corrugated asbestos building.
He is standing in the middle of the back row.
Others who enlisted at the same time, 7th December 1915, include the following, and may appear in the photo, were;
57432 HALL Bernard John
57433 JONES Albert Edward
57434 HERRICK Arthur Cecil Cpl.
57435 MORRELL Alfred
57436 PETT Thomas William Frank
57437 WARD Percy Haddon
57438 BARKER Graham
57439 ROBERTS Owen John
57440 ROBERTS Hugh Henry
57441 WILSON Albert
57442 WOODBRIDGE Leonard
57443 ROBBINS John
57445 GRIFFIN Eric Cpl. M.M.
57446 ALDER Edward Thomas
57447 BARNES Joseph
57448 TURNER Arthur
57449 WOOLLEN George Clarence
57452 MEADOWS Leonard
57454 HEWETT Wallace Horatio A/Sgt

I'd love to have information/names of others who appear in the photo, and info on those who are listed as joining at the same time
Many thanks Ken Davies

[Penmon]

Additional memo to the above. My grandfather Owen John Goodman Roberts was born on Anglesey. Information relating to his life and Great War involvement can be found under his name on my family history website. - Click on the globe icon under my details on the left.

[Bilge]

Do you know what company he served with?

The Machine Gun Corps is created

On 2 September 1915 a definite proposal was made to the War Office for the formation of a single specialist Machine Gun Company per infantry brigade, by withdrawing the guns and gun teams from the battalions. They would be replaced at battalion level by the light Lewis machine guns and thus the firepower of each brigade would be substantially increased. The Machine Gun Corps was created by Royal Warrant on October 14 followed by an Army Order on 22 October 1915. The companies formed in each brigade would transfer to the new Corps. The MGC would eventually consist of infantry Machine Gun Companies, cavalry Machine Gun Squadrons and Motor Machine Gun Batteries. The pace of reorganisation depended largely on the rate of supply of the Lewis guns but it was completed before the Battle of the Somme in 1916. A Base Depot for the Corps was established at Camiers.

[Bilge]

http://www.1914-1918.net/mg_units.htm

53rd MG Company Formed Grantham. Moved to France and joined 18th Division, 13 February 1916 at Ribemont. Moved into No 18 Bn, MGC 16 February 1918.
54th MG Company Formed Grantham. Moved to France and joined 18th Division, 13 February 1916 at Ribemont. Moved into No 18 Bn, MGC 16 February 1918.
55th MG Company Formed Grantham. Moved to France and joined 18th Division, 13 February 1916 at Ribemont. Moved into No 18 Bn, MGC 16 February 1918.
56th MG Company Formed Grantham. Moved to France and joined 19th Division, 14 February 1916. Moved into No 19 Bn, MGC 14 February 1918.
57th MG Company Formed Grantham. Moved to France and joined 19th Division, 14 February 1916. Moved into No 19 Bn, MGC 14 February 1918.
58th MG Company Formed Grantham. Moved to France and joined 19th Division, 14 February 1916. Moved into No 19 Bn, MGC 14 February 1918.
59th MG Company Formed Grantham. Moved to France and joined 20th Division, 3 March 1916. Moved into No 20 Bn, MGC 15 March 1918.
60th MG Company Formed Grantham. Moved to France and joined 20th Division, 3 March 1916. Moved into No 20 Bn, MGC 15 March 1918.
61st MG Company Formed Grantham. Moved to France and joined 20th Division, 3 March 1916. Moved into No 20 Bn, MGC 15 March 1918.
62nd MG Company Formed Grantham. Moved to France and joined 21st Division, 4 March 1916, at Armentieres. Moved into No 21 Bn, MGC 24 February 1918.
63rd MG Company Formed Grantham. Moved to France and joined 21st Division, 4 March 1916, at Armentieres. Joined 37th Division with Brigade, 8 July 1916. Moved into No 37 Bn, MGC 4 March 1918.
64th MG Company Formed Grantham. Moved to France and joined 21st Division, 4 March 1916, at Armentieres. Moved into No 21 Bn, MGC 24 February 1918. > War Diary
65th MG Company Formed Grantham. Embarked Devonport 5 July 1916 for Salonika, and joined 22nd Division, 14 July 1916. 
66th MG Company Formed Grantham. Embarked Devonport 5 July 1916 for Salonika, and joined 22nd Division, 14 July 1916. 
67th MG Company Formed Grantham. Embarked Devonport 5 July 1916 for Salonika, and joined 22nd Division, 14 July 1916. 
68th MG Company Formed Grantham and joined 23rd Division, 4 March 1916. Moved into No 23 Bn, MGC 1 April 1918.
69th MG Company Formed Grantham and joined 23rd Division, 4 March 1916. Moved into No 23 Bn, MGC 1 April 1918.
70th MG Company Formed Grantham and joined 8th Division. Moved to 23rd Division, July 1916. Moved into No 23 Bn, MGC 1 April 1918.

[Penmon]

Bilge - Many thanks for all your wonderful information. It's amazing to see so many divisions formed and deployed to France. How many thousands of young men were involved in all this I wonder? Poor souls.
All I know is that my grandfather worked (loading) the Vickers Machine Guns, and served at Ypres, Arras and Cambrai according to my family.
I have no great detail of his service, but the following hand written telegram was received by his mother (telegram erroneously states 'husband' but should read 'son'). It was sent as a result of my grandfather being hit by shrapnel on the 17th November 1917.

November 30th, Dear Mrs Roberts
You may have heard by now that your brave husband has been wounded. I just write at his request to say it is not a dangerous wound. It is in the chest.
He was very brave and did grand work. We have God to thank that his life has not been asked for.
Yours sincerely, C.C. Griffiths C H E Chaplain.
3 Cavalry Brigade B.E.F.
(Canon Cuthbert Cyril Griffiths who was awarded the Military Cross)
In addition to service medals, my grandfather received a Silver War Badge (B15544 ROBERTS Owen John)
Some other recipients at the time wrere;
B15537 BAYMAN William
B15538 WILLIAMS James Henry
B15539 TURNER James Williams
B15540 DICKINSON John
B15541 BENNINGTON Geo Stanley
B15542 KARL George
B15543 MUNCEY Herbert
B15544 ROBERTS Owen John
B15545 CHALLIS George
B15546 SPIERS William
B15547 McWILLIAMS Alexander
B15548 FULCHER Frank

Many thanks once again