As recruiting had been slow and a Negro regiment in New York was looked upon as an experiment, Colonel Hayward was obliged to secure the needed officers from among his friends in the 7th New York, the Motor Battery, Squadron A and other organizations.

By this time the enlisted strength had grown to 1,200.

On April 8, 1917, two days after the United States entered the war, the regiment was inspected by Federal officers and a week later was recognized as a regular unit of the Federal Guard.
But, as the Colonel expressed it, they were a "street urchin of a regiment." They had no armory, no place to drill except in the open and no place where more than a single company at a time could meet.

In his post-war observations, the Colonel has noted that when the regiment returned to these shores and was feasted and entertained by the people of New York in the 71st regiment armory, it was the first occasion on which the old 15th was ever assembled under one roof.
After its Federal recognition the regiment was sent to the Peekskill rifle range to learn to shoot, a valuable experience as developed later.
Many of the boys became expert marksmen, a skill that became of precious value to them and their comrades.
In June, 1917, they went to a war strength of 2,000 men and 56 officers.

One battalion did pioneer work at Camp Upton, another at Camp Dix.