|
Jesse's Hunting > Gun Room Articles > Gun Room Archives > The "Hummin' Boar"
The "Hummin' Boar"
Tim Mancillas - JHO Pro Staff
February 05, 2004
“Hey, Tim. I’ve got a new idea for a barrel. One will be shipped to you as soon as they get back from the laser engravers. Let me know what you think.”
"Huh? Uhh…okay, sure Rick."
That’s essentially how this project started.
Rick Sanborn at Green Mountain Barrel Company routinely pops new ideas past me (someone actually values any of my opinions!) and this was his latest. Imagine my surprise when I arrived home from work one day and found a long brown box sitting on my porch. It was not nearly as much surprise as when I opened it, and laid eyes on Green Mountain’s latest addition to their already dense listing of replacement Ruger rimfire barrels.
First off, most shooters are probably asking themselves “What in the heck is a ‘Running Boar’ barrel?”
In the early 1900s there used to be an Olympic shooting competition called the Running Boar Competition. As the name implies, it consisted of a metallic or paper silhouette (in the shape of a boar) that moved along rails perpendicular to the shooter at 50yds. The challenge of this event was to hit a moving target at 50 yds, in the vitals, while the target was only presented from anywhere to 2.5-5 seconds. The target would appear briefly between two bushes, presenting a realistic fleeting target that you’d typically see in the backcountry. The shooter had 30 rounds of ammunition for this event.
Ensuing political correctness and the lack of participation ended the Olympic event. At the time though, the rifles used in the event were .22LR bolt-action rifles and often sported weighted muzzles. Thus the term “Running Boar Barrel” came about as a reference to a sporter barrel with a weighted muzzle.
The next question shooters ask is “So what’s the deal with the big muzzle?”
The answer is actually quite simple when you think about it.
At the turn of the century, barrel making, the steels used, and the stresses induced by contouring and rifling still remained in the realm “voodoo magic” and “trade secrets”. At the time, barrel makers learned their specific barrel making processes by trial and error, with very little understanding of why it worked. When barrels were rifled back then, a great deal of stress was often induced during the process. The cutting of the grooves left the metal with a stress that tended to want to push out (away from the rifle tooling). This was true even after the cutting was done. When a barrel was then contoured/profiled, the muzzle end had a tendency to “flare” out or become slightly larger. This was because the stress induced was (largely) equal across the length of the barrel blank, and when contoured to a sporter profile, there was less metal surrounding the muzzle end to contain (or hold in) the stress. In many cases there was enough induced stress that it forced the metal out, actually increasing the diameter of the bore at the muzzle. Most shooters automatically understand that this is bad…very, very bad.
The crown and the last 2-4 inches of the barrel are the most important, as they are the last things that the bullet touches as it sails out into the air and makes its journey down range. Shooters, not wanting to lug around a “bull barrel” (or heavy barrel) but still wanting the same accuracy of one, decided to try and leave the muzzle end the same outside diameter as the receiver end. Voila! The “Running Boar” barrel was born! When shooters starting using this profile they found that they could hit moving targets much easier and more consistently. Now how is that possible?
Most of us have been exposed to the three basic laws of physics in high school. Without reciting all of them, we’ll skip to the third one, which states, “A force in motion tends to stay in motion, until acted upon by an outside force”.
One of the chronic problems shooters face with shooting a moving target is what is referred to as “follow through”. As the shot is fired, a shooter tends to relax their muscles and stop moving their forearm. The “Running Boar” profile tends to help negate some of this, using that third law we just talked about. The extra weight on the end of the barrel requires more energy to stop, so it tends to want to keep going in the direction of the swing. Also, although the weight at the muzzle is fairly light, centrifugal force and the speed of the swing amplify it.
Think of it this way; a 2” x ½” diameter bolt weighs only a few ounces. But if you attach a piece of string to it and spin it around in a circle, it feels much heavier (the faster you swing it around, the heavier it feels). The same principle applies to a shooter’s swing on a moving target. So, when the shooter fires the shot and starts to relax, the muzzle’s weight (amplified by centrifugal force) tends to want to continue on the arc of the swing. End of history and science class! (I promise!)
The barrel I received from Green Mountain was a stainless steel 22” barrel with a roughly 4” weighted end. Unique to Rick’s concept barrel was the fluting that was done to the muzzle. Though it may seem counter-productive to reduce weight at the muzzle (one of the main reasons for a ‘Running Boar’ profile), it has left the muzzle nicely weighted, while still retaining the rigidity of a solid and weighted muzzle. This twist to the old “Running Boar” profile has made it a delight to carry in the field as well as very appealing to the eye. And what better way to introduce it then in the new (relatively speaking) .17 HMR caliber?
The rifle (a Ruger 77/22M) with nothing more than a Timney sear installed, has performed every bit as well as other heavy barreled rifles I have in this caliber. After initial break-in (typically 100 rounds, give or take 20) this “hummin’ boar", as I’ve taken to calling it, routinely delivers sub-MOA groups at 100yds. From a more practical point of view, it was a joy to install because I didn’t have to relieve the barrel channel to get the barreled action to drop back into the stock. (Rick has wisely used the original Ruger profile, except for the muzzle of course.)
On life sized rabbit targets, this “Hummin’ Boar” was able to routinely deliver 3-5 shot clover leaf clusters into the head at 100 yds w/ Hornady VMAX ammo. The image above shows an average group at 100 yards.
As a side note, despite reports of the 77/22M’s two-piece bolt (which can reportedly affect accuracy), this rifle was surprisingly accurate with no tinkering (aside from the previously mentioned Timney sear). The rifle was quite literally pulled out of the box, barrel mounted, sear installed, the scope mounted, and then cleaned and shot! (Took about a whole 30 minutes to do.)
Also, I want to set the record straight for those skeptics out there. Rick and I have an understanding when it comes to me independently testing his barrels and QC. When he ships a barrel to me, he ships what “Joe Shooter” gets. He (literally) gets up from his desk, walks down to the plant floor and randomly grabs a barrel out of the pile from a production run and then has it sent to me. Now in my book, that says something for his and Green Mountain’s integrity and the confidence they have in the products they supply to shooters. Add to the fact that they are priced so just about everyone can afford one, and I am hard pressed to find anything wrong with their service and quality.
All in all, I was very impressed by this rifle in this configuration. It has fast become the rifle of choice when I’m heading out to the local agricultural fields in pursuit of some pesky desert ground squirrels. The fit, feel and aesthetics are something to behold! Nope, no $350 rimfire barrels for me. I’ll take a Green Mountain barrel any day of the week over the more high priced ones out there, take the money I saved and put some nice glass on top of my new rifle.
If you decide to go the route of the “Hummin’ Boar” I will give you one warning…Buy lots of ammo! With the feel and weight of this rifle, you’ll be getting a lot of use out of it! Who knows, maybe there’ll be a resurgence of interest in the “Running Boar” competition? It sure would be fun to give it a go!!!
Tim Mancillas
JHO field writer & pro staff
|
