Battery K is honored by two identical monuments at Gettysburg shared with Battery F.

1861
October Duty in the Defenses of Washington, D. C. Attached to Battery F, 3rd United States Artillery, and assigned to the Artillery Reserve, Army of the Potomac
1862
March Ordered to the Virginia Peninsula
April 5-May 4 Siege of Yorktown
May Attached to 5th Brigade, Artillery Reserve, 5th Army Corps, Army of the Potomac
June 25-July 1 Seven days before Richmond
July 1 Malvern Hill
July-August At Harrison’s Landing
August 16-23 Moved to Fortress Monroe, then to Alexandria
September Duty in the Defenses of Washington attached to Artillery, 1st Division, 3rd Army Corps, Army of the Potomac
September 22 Ashby’s Gap
December 12-15 Movement to Falmouth, Va. Battle of Fredericksburg
1863
January-April At Falmouth
April 27-May 6 Chancellorsville Campaign
May 1-5 Battle of Chancellorsville
May Attached to 1st Regular Brigade, Artillery Reserve, Army of the Potomac
July 1-3
Battle of Gettysburg

The battery was commanded at the battle by Lieutenant John C. Turnbull. It brought 145 men and six 12 pounders to the field, and lost 1 officer and 8 enlisted men killed, 14 men wounded, and 1 man missing. The battery lost 4 guns captured during the fighting along Emmitsburg Road on July 2, but they recovered in late afternoon.

From the two monuments at Gettysburg:

July 1 Took position on crest of hill near General Meade’s Headquarters.

July 2 Moved to a position on the right of a log house on the Emmitsburg road with General A. A. Humphreys’ Division Third Corps. Engaged here but was compelled to retire with the loss of 45 horses killed and 4 guns which were afterwards recaptured.

July 3 Went into position near Taneytown Road on the left of Cemetery Hill.

October 9-22 Bristoe Campaign
November 7-8 Advance to line of the Rappahannock
November 7 Rappahannock Station
November 26-December 2 Mine Run Campaign
November Attached to Artillery Brigade, 5th Army Corps, Army of the Potomac
1864
February Consolidated with Battery C. Attached to 2nd Brigade, Horse Artillery, Army of the Potomac
May 4-June 12 Rapidan Campaign
May 5-7
Battle of the Wilderness
May 8-21
Spotsylvania Court House
June 1-12
Cold Harbor
June 16 –
August 5
Siege of Petersburg
August 7-
November 28
Sheridan’s Shenandoah Valley Campaign. Attached to Horse Artillery, Army of the Shenandoah, Middle Military Division
August 11 Near Winchester
August 25 Near Kearneysville
October 19 Battle of Cedar Creek
October-April Duty in the Shenandoah Valley
December Attached to Horse Artillery Reserve, Army of the Shenandoah
1865
April To Defenses of Washington, D.C. Attached to Horse Artillery Brigade, 22nd Army Corps until August