Here's a copied and pasted article from somewhere that I read from time to time that has proven to be as accurate in the field as I've been able to find. It takes time to do this, but it does work. Enjoy.
Walla Walla hunter Corey Reynard has taken trophy bull elk with bow, muzzleloader, and centerfire rifle. He is also one of the most prolific gatherers of shed antlers in the Blue Mountains.
During the past 11 years, Corey has retrieved more than 800 elk antlers and has become adept at judging the size of trophy bull elk racks. He offers six quick steps that beginners can use to estimate the gross B&C score of a bull elk's rack.
1. Count the points on each beam. Trophies generally will be 6x6 or larger.
2. Brow tines that curl upward and extend as far out as the bull's nose are about 18 inches long. Estimate the length of the brow tines and use that as a reference to estimate the length of all the other points on the bull's rack. Total up the length of all the points on the rack in inches.
3. The main beam of most mature bulls, from the antler base to the bottom of the fourth point, is about 30 inches long. Using that for reference, estimate the length of the remaining antler beyond the fourth point, and add the two together to get a total beam length. Most trophy bulls will have main beams over 50 inches in length. Total the estimated length of both beams in inches.
4. Add 40 inches for spread, deducting 5 inches for a narrow rack and adding 5 inches for an exceptionally wide rack.
5. Add 25 inches for mass for each beam. Add 5 additional inches per beam for an exceptionally heavy rack.
6. Total the estimated length of all points, the length of each beam, the width of the rack and the mass for each beam. This gives you an estimated gross B&C score.
According to Reynard, bull elk across the Blue Mountains have a lot of "trash," or kicker points, on their racks. These extra points make for distinctive trophies, but also create deductions that might keep a bull out of the record book.
