All three of these men are recorded as being in Co. A, 1st Texas Sharpshooters.

Unfortunately, my access to CW Service records have no listing of men with 'F'
surnames.

George Martin

1st Battalion, Texas Sharpshooters (Burnett's)
1st Battalion Sharpshooters completed its organization in Grayson County, Texas, during the spring of 1862. It moved east of the Mississippi River, was assigned to Maxey's Brigade in the Department of Mississippi and East Louisiana, and took part in the Vicksburg operations. On December 17, 1863, it was reported that the unit had been transported back across the river in small groups between Federal naval patrols. It then served in the Trans-Mississippi Department and sometime during the spring of 1864 was mounted. The battalion went on to participate in various conflicts in Arkansas and the Indian Territory, and for a time was on provost duty at Marshall, Texas. It probably surrendered at Doaksville, Indian Territory on June 23, 1865. Major James Burnet was in command.