Hi yo6oej,
without seeing the arrow head in my hand as it were an accurate id is very hard. But having said that the " experts" at the archery club I go to said that your example was possibly a type 14 swallow tail or even a curved broadhead. The following will explain the use for the design of your arrowhead:-
"The Broadhead
Broadheads in general are characterized by a wide and flat profile with long cutting surfaces, primarily suited for slicing through flesh. Early broadheads used by the Anglo-Saxons were not "barbed" and were used for hunting large animals like boar, deer and elk as well as against men in times of War.
Later broadheads were more often "barbed" so that once the arrow penetrated, movement by the prey, regardless of man or beast, would cause continued penetration and internally slice muscle tissue and organs. When attempting to remove a barbed broadhead, one would have to break off the fletching to reduce the chance of infection and push the arrow through. Simply withdrawing the barbed broadhead would cause it to lodge into the tissue causing tearing and greater damage and often the head was not pinned to the arrowshaft so if the arrow was withdrawn the head would come loose and remain in the body.
A variety of these barbed type heads were common. Small straight broadheads were used for hunting small to medium game and human targets during War. This type was used at the Battle of Bosworth. Larger straight broadheads were used for hunting medium to large game.
Curved Broadheads were somewhat larger and used for hunting larger game at short distances. The curved cutting surface more easily sliced muscle and flesh to cause severe bleeding and immobility. These were sometimes used against horses to severely reduce the mounted knights advantage in combat. To maximize the cutting surface the Swallowtail broadhead featured extremely long barbs. They flew well and cut deep and were used in the Battle of Agincourt. "