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Field Judging - Mule Deer and Blacktails


The major features that make up a B&C score for mule deer and blacktails are: F - main beam length, G - point lengths, H - circumferences, and D - Inside Spread.    

Mule deer may not have as much going on above their heads as other members of the deer family, like elk and moose, but judging them in the field can be just as tricky. Accurately field judging a mule deer buck’s trophy status starts with knowing the basics of scoring a mule deer. Under the Boone and Crockett Club’s scoring system, the gross score for a typical mule deer is the sum total of measurements of his inside spread, length of his main beams, length of points, and eight mass or circumference measurements. By definition, a typical mule deer will have four points per side, plus eye guards. Under field conditions we don’t always have the time to pull out a calculator, however, there are a few things we can quickly look for to determine whether a buck would be a record book qualifier.

Once you’ve located your buck the first thing to check is his overall frame. This is the part where, “If he looks big, he is big” can come into play. A buck’s frame takes into account all factors used in scoring — the inside spread, length of points, length of the main beams, and mass. If you’re looking at a high racked buck with long points and a spread past his ears, you just might be looking at a buck that warrants a full evaluation. As a rule, high, wide, and heavy is what to look for, especially if you’re beyond trophy and thinking record book.

After frame, try and get a clean look at the number of points, fork depth, and symmetry. Any additional or “abnormal” points are subtracted from the typical score. However, if there are enough abnormal points, a buck may be scored as a non-typical and the length of the abnormal points are added to the score. The overwhelming majority of bucks that make the book are five-point bucks (western count — four points per side, plus the eye guards). 

A buck with good eye guards (3+ inches) is a bonus. If he is at least a 5x5, including the eye guards, move on to fork depth. Deep forks translate into long tines and high scores. The deeper his forks, front and back, the longer his tines will be.

While sizing up his forks, pay attention to fork symmetry. Do the back forks and front forks match their counterparts on the opposite antler in depth and tine length? In scoring, symmetry is a factor. It is common to see bucks with strong back forks but weak fronts (crab claws) and vise-versa. 

Next, check for mass. The mass or circumference of the main beam is also a consideration in scoring, but it can be tough to judge in the field. Mass can be estimated by comparing the circumference of the antler to the buck’s eye. A mule deer’s eye will measure about four inches in circumference. By using his eye as a gauge you can visualize whether his bases and main beams are at least 4-inches or larger. Heavy bases (6+ inches) with this kind of mass carried out through his main beams (5 to 4 inches), means a buck will receive high marks in the circumference category. 

Your last check is spread. By now you’ve already accessed his spread when checking his frame, but it will help to pin down a spread measurement before you tally everything. To accurately judge antler spread, we can use a buck’s ear width as a gauge. On the average mature mule deer buck, with its ears in an alert position, he will have an ear span of 20 to 22 inches tip-to-tip. But I have measured large specimens with ear tip to tip spans up to 26 inches. However, if you always use the 20 to 22 inch estimate your buck is less likely to suffer “ground shrinkage.” So with this estimate a buck’s rack past his ears by two inches means an inside spread in the neighborhood of 24 inches — more than enough to put him in the book if the rest adds up.


After judging all these antler features you should be able to put your buck into one of three categories; obviously a shooter and book contender, a buck on the bubble that may require actually adding up the numbers to see if he will make 180 (B&C typical minimum), or just one heck of a nice buck. If he’s on the edge, you might have to put a number on each feature that counts in final scoring and mentally add them up for a rough score to make your decision. Here, you can use his ears again to estimate each number. On most mature bucks it is approximately eight inches from the white spot at the base of the ear to the ear tip. If you visually superimpose this feature to the antler, you can accurately estimate things like length of main beam, height of the rack and length of the points.


There can be a lot of hurdles to overcome in accurate field judging. Getting enough time to look your buck over closely is one. Seeing all the angles so you can count points and access fork depth is another. There are also a few “X” factors that can throw you a curve, like antler coloration and background. Bucks sporting darker horns can appear to have more mass than a tape can give them credit for. Conversely, lighter colored antlers can appear to be thinner than they really are. Background can also trick you. If your buck is standing with snow as a backdrop, antler mass can appear greater. If he is standing in the shadows or in low light, his antlers can also appear to be thinner. Another common illusion in all field judging is the power of your optics. If you are viewing, at fairly close range, with your spotting scope on 60x, even an average 5x5 can look like a monster. Back off your power to a reasonable setting so you can compare him to his body features.

Bucks on the move leave little time for a really good look. You may not be able to get past frame and mass before you have to make a decision. Bucks traveling away from you always appear bigger than they are, and watch for other bucks. Having other bucks in view to compare with can be helpful. They can also trick you if you don’t pay close attention to how big they really are compared to the best buck in the bunch.

Also, if it’s been a while since you’ve seen a quality buck, either from season to season, or if you have gone a few days on the same hunt without seeing one, the first buck you see may seem bigger than he really is. If you have the time, settle down and run your mental checklist.

Lastly, a 30-inch spread is the ideological benchmark most mule deer enthusiasts look for in a trophy. Often times outside spread is all that gets noticed, as illustrated by my new-found hunting buddy mentioned earlier. Keep in mind, spread looks good on the wall, but in scoring, inside spread between the main beams is all that counts and it’s only one measurement. There are plenty of bucks in the record book with 25-inch inside spreads.

As with all acquired skills, accurate field judging comes with practice. The more bucks you have a chance to put a mental tape on the better you will become at judging them before deciding to tag ’em or pass ’em. Nothing beats sizing up live game under field conditions when the pressure is on. This builds confidence and speed in your assessment. But, if you are like most of us, time in the field seeing trophy-class bucks can be hard to come by. The next best thing is to estimate the score of mounted heads, then put a tape on them. You’ll be surprised how close you can come with a little practice.



World's Record Typical mule deer scoring 226-4/8 points


Typical mule deer scoring 185-3/8 points



Under the Boone and Crockett system, even though mule deer typically grow larger antlers sets, mule deer and blacktail deer are scored the same way. Past this obvious antler size difference there are still a few thing to look out for specific to field judging each species of blacktail

Of the two species, in some locals, the Columbia blacktail can grow antlers comparable in size to that of mule deer. Knowing the record book history of the region you are hunting in is the first tip in field judging Columbia blacktail. The next is 4X4, not counting eye guards.

In field judging blacktails, points are everything, even more so than the other deer species. The smaller overall antler size of blacktails means mass, inside spread, and length of mainbeams are reduced to the point that even an exceptional measurement from one or two of these areas will not compensate for less than four points or an unbalanced number of points per side.

For Columbia blacktail there are very few 3x3, not counting eye guards, in the record book. Speaking of eye guards, just like in mule deer, eye guards or G1s are not always present, even less so in both specie of blacktail. If eye guards are present over one-inch, they’re a bonus and will add to the final score. In some cases, eye guards can make the different in putting a buck over the minimum entry score if everything else is present. 

The record book does include 3x4 Columbia blacktails, not counting eye guards, more so than 3x3s, but not that many. For deer the antler size of blacktails, this unbalance is costly when adding up score.

The Sitka blacktail is the smallest of the three mule deer in antler size. Because of this, when it comes to score, the loss of one point on one side and no eye guards is costly. There are no 3x3 Sitka blacktails in the book. Four by fours make up only 12-percent of entries to date, with 4x5s 13-percent, and 5x5s (eye guards included) making up 66-percent.

The bottom line for field judging blacktail deer is check for four-points per side, not counting eye guards first. If you are looking at a buck with four per side you’re looking at a trophy by most standards. By record book standards, past 4-points a side, the rest will need to add up just like in mule deer – length of points and mainbeam, mass, and inside spread.



World’s Record typical Columbia blacktail deer scoring 182-2/8


Typical Columbia blacktail deer scoring 129-7/8


Field Judging

One of the best ways to improve your field judging skills is to get a strong understanding of scoring a particular animal. 

Check out B&C's newest scoring manual...

How to Score North American Big Game, 5th Edition

A Joint Official Measurers Manual for the Boone and Crockett Club and Pope and Young Club

While the definition of a successful hunt is left to its participants, the Boone and Crockett Club scoring system remains the benchmark for identifying mature big-game animals and healthy big-game populations.


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