Dall Sheep Hunting in Alaska
Dall Sheep Hunting
Judging Full-Curl Rams

The Alaska Game Regulations define a full curl horn as "the horn of a male (ram) Dall sheep, the tip of at least one horn has grown through 360 degrees of a circle described by the outer surface of the horn, as viewed from the side or with both horn tips broken, or the sheep is at least eight years of age as determined by horn growth annuli."
It takes an average of 8 years for the ram's horn tip to form a circle as seen from the side. Rams with both horns broken are included in the definition of full curl. These rams are usually very old and they will die before their horns will again grow to full curl.

Ram horns (which are never shed) grow in a helix, like the threads of a bolt, out from the head. For a ram to be full curl, the outer surface of the horn as viewed from the side must describe this perfect circle.
You can determine the degree of curl of any sheep horn by looking for the outline of the
perfect circle and seeing how far around that circle the tip has grown. A 7/8 curl ram will have horns
that describe 7/8ths of a circle. Three quarter (3/4) and 1/2 curl rams will have horns describing
smaller portions (arcs) of the circle. Very young rams have 1/4 curl horns, similar to those of ewes.

It is important to look for the perfect circle. Less-than-full curl horns can be viewed from an angle that makes the horn tip line up with the base. When viewed this way, the outer surface of the horn will NOT form a perfect circle. Instead it will form a flattened circle, or ellipse.