Do Antlers and Horns Really Shrink?

Whether you found an ancient set of antlers in your uncle’s barn or you just killed a massive whitetail, you’re going to have to wait 60 days before getting a true measurement. Allow us to explain why. 

In the spring of 2014, retreating snow drifts in Alberta revealed a massive bighorn ram that died of natural causes. Alberta wildlife officials green-scored it at more than 209 points, and it appeared to be a new world record—at the time. The celebratory Molsons couldn’t be cracked right away, though. Everyone had to wait the mandatory 60-day drying period before official measurements could be taken. During this drying period, the horns had to air dry at “habitable” room temperature (60 degrees F/15 degrees C or greater). This goes for hunter-killed animals as well as “pick ups” like the ram in question. Once the ram started to thaw, the horns started to shrink. 

Over those 60 days, the horns shrank an astounding four inches in net score. Every measurement was smaller on both horns. It’s still an amazing ram at 205-7/8 and ranks tenth of all time in the Boone and Crockett Records. But what happened? 

Apparently, the horns had absorbed quite a bit of moisture from being buried an entire winter. It was very cold when the ram died, and the moisture inside the ram’s horns froze. Water expands when frozen, and it stayed frozen even as officials from Alberta put a tape to it, says Justin Spring, director of big game records for the Boone and Crockett Club. 

An Alberta wildlife officer fills out the necessary paperwork for a bighorn sheep found near Gregg River. The ram's final score is 205-7/8 points, 4 inches less than when it was green scored.... before the 60-day drying period. Click here to see the official score chart (available for FREE to website subscribers).

Unlike antlers, horns are made of keratin—the same compound found in human fingernails. Over time, horns will continue to shrink as they continually dry. If you want to keep your record-book mountain goat nearly as big as the day you took it, please don’t put it over the fireplace. While it looks great, the heat will sap any moisture left in those horns. 

Antlers are, initially, made of living tissue as well, which means they do retain some moisture. As antlers dry, they also shrink, but each trophy is slightly different. Antlers from a bull killed just after it rubbed off the last of its velvet will generally show more shrinkage than antlers from a bull taken on a November hunt.

Long-time B&C Member and Official Measurer Fred King (second from right) has been a part of nine B&C Judges Panels and served as the chairman of the panel for the 24th Big Game Awards in 2001.

That Alberta ram is an extreme example of shrinkage, but the takeaway here is that antlers, horns and even skulls can and do shrink. For this reason, the Boone and Crockett Club requires a 60-day drying period for any animal to be entered into the record system. You can read the drying period policy for both the Boone and Crockett Club and Pope and Young Club here. 

Why Dry? 

When the Club announced their official scoring system to the world in 1950, members agreed that some sort of drying period was necessary because many of the trophies scored prior to 1950 had been drying for decades. Committee members felt the only way to be fair to those trophies was to require that all trophies go through a drying process.

To dive a little deeper into the drying period, I spoke with Fred King, who’s been a Boone and Crockett Official Measurer (OM) since 1984. He lives near Bozeman, Montana, and he gets to see and measure plenty of really big animals. King notes a couple of interesting things about the drying period. 

First, the drying period was originally called a waiting period to allow all trophy owners an equal chance to contact an OM. Back before cell phones and the internet, it could be tough to track down an OM in less than two months. Now, though, all you need to do is check out the OM locator and find the OM nearest you. Back in the day, the waiting period gave hunters time to find an OM. 

Second, King stresses the need for a solid baseline. “The drying period is simply based on an equal starting point for all trophies to be measured against,” he says. Take the frozen Alberta ram. Without the 60-day drying period, what’s stopping a hunter from harvesting an awesome ram or bear, then tossing it in the freezer for a few months to get an extra half-inch or two? Today, the waiting period helps to even the playing field as much as possible to provide consistency in the records. 

“The Boone and Crockett Club is concerned about the credibility of the score that the trophy gets,” said King. “We teach new OMs that consistency is key from one trophy to the next.” 

A Note About Allowable Shrinkage

For trophies that are re-scored for verification purposes after an official score has been accepted, the Club has an allowable shrinkage rule. Most commonly, these are trophies invited to be confirmed by a judges panel, such as the upcoming scoring panel at the 31st Big Game Awards in April 2022. At times, there can be a three-year wait or more from the time the animal is killed until it can be scored by the panel. Keep in mind, the animal has already been scored by an Official Measurer after the 60-day drying period. Panel scoring is simply a way to confirm the original measurements taken by the OM. This panel process ensures consistency among the highest scoring entries in each category, providing records staff the ability to review Official Measurers’ methods and make any necessary corrections. 

Until the scoring panel convenes, the antlers, horns or skull may shrink a little more—even after the 60-day drying period. So what happens when the panel score is lower than the OM’s score? If the smaller measurement is within “allowable shrinkage” for that trophy category, then the original OM’s measurement will be confirmed.  

“In the end, shrinkage comes down to moisture content,” said Spring. “The 60-day drying period gets those antlers, horns or heads down to a minimum. And again, it all comes down to consistency within the records.” 

PJ DelHomme is a writer for Crazy Canyon Media in Missoula, Montana. He regularly contributes content to the Boone and Crockett Club as well as national and regional publications.