Bethleham Steel test site in WWI

According to Cape May Point by Joe Jordan, Bethlehem Steel tested ammunition at a site on Higbees Beach, NJ, in World War I. There is some concrete visible about 100 feet offshore and a few hundred yards east of the rock piles that protect the canal used by the Cape May Ferry. A friend told me that Bethlehem Steel had a gun platform that was used to fire (test) ammunition. Some of the ammunition, according to my source, was for Russia and some for the US. Although the remains of the gun platform are now in the water, erosion probably has taken its toll and the original gun platform was most likely on the beach or even back on land. Does anyone have a picture of the gun and information on the caliber of shell fired? I believe Bethlehem made shells for the 9.2 inch MKII howitzer. The shell weighed approximately 290 pounds and had a range of 7 miles. I could have been fired in the direction of Lewes, DE, some 14 miles away. Bethlehem manufactured other ammo including 75mm.
Thank you.