Beware: long post
Knives would be similar, but not the same. Think archery...all the arrows are similar, but not the same(both for one competetor, and between competitors). Each competitor shall provide at least 5 knives, with up to 3 spares, should one break. Competitors will be able to 'trade in' spares between rounds (in case a tip breaks, or is dulled, etc)
Each knife shall be between 10 and 14 inches in length, and between X and X oz weight. Made of steel. Each knife shall have one point on the pointy end, and one non-pointy tang end(no throwing stars). Knives may be single or double edged, and may or may not be *sharp*, but must have a blade(no throwing spikes--maybe a seperate comp.) Handle may be scales, cord wrapped, or plain steel tang, but must be the same for all the competitor's knives. (this is to keep designs within reasonable parameters, but allow for engineering improvements)
Each of these knives shall be reasonably the same. (within 1/4" of length of each other, within 2 or so oz? of each other, blade/handle ratio the same for each knife, etc) (No special knives for different ranges.)
It would be advantageous for the competitor to make each knife *exactly* the same, so they have that much more control.
Rounds shall consist of 5 throws at 5 bullseyes (to prevent knife hitting knife) equally spaced on an end-grain pine target, to be changed after each round. Bullseyes would be something like a 1/2" circle in a 2" circle in a 6" circle on a 2.5'x 2.5' target in front of a backstop.
If they start a round using handle/blade throw, they use handle/blade throw for the rest of the round. They may switch for the next round.
Accuracy comp:
One round at 5yds, 10yds, 15, 20.
Masure the distance from the center of the bulls-eye to the nearest part of the knife stuck in the target, add all the distances up, and the person with the lowest score wins.
Distance comp: start at 25 yds, each person throws 5. move back 5 yds after each round. Each competitor must stick 2 of 5 in the 2.5'x2.5' square at each range to continue the next 5yds.