The regiment was attached to Stevens' 3rd Brigade, W. F. Smith's Division, Army of the Potomac, to March 1862.

This was because Neill's 3rd Brigade of VI Corps was one of the last to reach the battlefield on Thursday, July 2, and was held in reserve on the Baltimore Pike at Rock Creek.

On Friday, the third day of the battle, the brigade deployed to the north of the Pike on the east side of Rock Creek to push back Confederate skirmishers that were threatening the army's main supply and communications route.

[1] By the end of the first full year of hard campaigning, the regimented returned 846 Model 1842 smoothbore percussion muskets to the Adjutant General.

[14] The regiment reported the following survey result to U.S. War Department:[15][16] It appears they continued with a mix of Springfields and Enfields.