hmmm I'd wonder if it's a unknown Variety of Henning's Counterfeits
In the mid-1950s Francis LeRoy Henning of Erial, New Jersey minted what is now known as the “Henning” Nickel. He made counterfeit nickels dated 1939, 1944, 1946, 1947 and 1953. ... The 1944 Henning Nickel is easy to spot because of the missing Mint Mark. But the other dates 1939, 1946, 1947 and 1953 are more difficult.
but Because of the Low Silver Content of the War Nickels, It's most likely real.
& Yes probably a Beach Find