My hunt for antelope starts this week on Deseret, and I am still trying to figure out how to judge a goat. If anyone has some photos of the size of bucks I need to be looking for I would appreciate it.
I am no expert, but I have been around some big antelope. I think cutters above the ears and what looks like mass. I like to look at shape also, liking the tips to curl in a little. Antelope seem to be the hardest animal to judge, but a big antelope just looks big. Best of luck and have a safe hunt.
My variation is 7 inches length from base to base of prong (this means prong will start just above the ears); 7 inches length from base of prong to ivory tips; 7 inch bases (about the size of making a circle w your thumb and bird finger), 7 inch mass measurement just below the prong (usually this very close to the base--sometimes even a little bigger), and 7 inches total in the two mass measurements above the prong (this is hard to calculate. I think you just have to look at enough horns to know what mass above the prongs looks like.)
Post your photos when you get back. You will have a great hunt