In the case of the Manchester's Volunteers, they tended to all be local men in local employment, so the obvious thing to do is to see if any of your family actually were and find out where they were living at the time.
The Volunteers who actually served in South Africa were really very few, when the Anglo Boer War became inevitable, the War Office received very many offers to raise companies for service, but, these were all declined, it was not expected to last all that long and there was no chance of the Militia being exhausted.
So really the Active Service Companies were the last to be formed, the War Office, had decided, I would think on cost grounds, that each company should be one hundred and fourteen strong, including four officers and would be attached to their regular battalions of the Army actually in South Africa.
This was intended to make up the short fall after these regular battalions had lost a company after conversion to the mounted infantry roll.
In the particular case of the Manchester Regiment, the 1st Volunteer Active Service Company was raised from the original first four volunteer battalions so you ended up with twenty nine men from the 1st Battalion in Wigan, twenty nine from the 2nd Battalion, twenty eight from the 3rd Battalion in Ashton Under Lyne and twenty seven from the 4th Battalion, both 2nd and 4th were from the city itself, as already mentioned and included William Kirkby, a clerk from Old Trafford, who I noted to you before.
From memory, their officers were Captain Heywood of the 2nd Battalion, who was in command, Lieutenant Darlington of the 1st Battalion and Lieutenant Howe from the 3rd Battalion, interestingly Howe was actually a Captain in the 3rd, but, to secure a place within the company had waived his rank.
The usual modus operandi was the signing of a short service engagement with the Army that allowed each volunteer soldier to actually service overseas, much like the Imperial Servicemen in the Territorial Force after 1908.
The company mobilised at Ashton on the 9th of February 1900 and left Southampton on the 14th and on the 14th of March they joined the 1st Battalion Manchester Regiment in Natal, on the 15th they marched up to Manchester Fort at Caesar's Camp!
The company remained with the 1st Manchester's and it's men were expected to perform all the duties of the regular soldiers and did end up taking casualties as a result, they were joined by drafts from the 5th and 6th Volunteer Battalions Manchester Regiment in due course.
The order to return home came in October 1900, but, this was later cancelled after they had left the 1st Manchester's, on the 29th of October they left for Elandsfontein where they would become part of the garrison until March 1901, from memory, they were stationed at Simmer and Jack mine.
The company was later deployed at Natal Spruit to replace a company of the Railway Pioneer Regiment, before being ordered home towards the end of April, again, from memory, Lieutenant Howe, who I mentioned before, decided to remain behind and sought a commission in the SAMIF, he clearly did not want to return to Ashton!
Anyway, I hope that gives you an idea of what went on and I wish you good luck with your family tree.