The Quest for the Two Mile Prairie Dog

By Steve Hugel
With permission from The Accurate Rifle Magazine.

February 2002

 

          


Each morning out on the prairie north of Pueblo West, CO finds Bruce Artus, and Kreg Slack preparing for an attempt to break their own world record for the longest shot on a prairie dog ever recorded, at two miles. Specialized super long range rifles, and associated equipment are just part of the equation. As necessary as they may be, nothing can replace motivation, determination, and perseverance evident on the faces of both shooters, as they watch and study the ever-changing conditions, patiently waiting for the rare opportunity needed to accomplish their record-breaking goal.

Not long ago out on the prairie north of Pueblo West, Colorado I found myself behind the hood of a pickup truck with my eye glued to the ocular of a Bushnell 36X spotting scope.  I was studying the area around gunsmith Bruce Artus’ 20” steel gong waiting for any sign of a bullet impact.  Finally a puff of dust rose from the dry, parched prairie maybe 10ft. or so to the side of the gong.  A few seconds later, another slightly less authoritative puff of dust also appeared in a different location close to it.  I glanced up as the shooters made a few windage and elevation adjustments on the micrometers that were an integral part of the extremely sophisticated ring/base system they were using.  A few seconds later, 2 more Sierras were launched again into the (upper?) atmosphere on their way to a point far north of our position.  Again I reattached my eye to the spotting scope watching in hopeful anticipation of a connection.  Mirage was already beginning to build even though it was still only about 60 degrees or so, and the sun hadn’t even come close to topping the eastern horizon.  All of a sudden through the scope I could see the “boil” make a slight directional change to the east, and I felt a breeze touch my cheek.  A slightly unappealing though not totally inaccurate expletive erupted from both shooters, Bruce Artus and partner Kreg Slack, as they remarked upon the ever-so-slight change in conditions.  Seconds later the bullets impacted downrange maybe another 10 ft. or so farther away than the first couple of shots.  Another micrometer adjustment, and a couple more big Sierras were off and running again.  And so it went for maybe 10 shots or so when Kreg spotted a prairie dog sitting atop his mound close to the gong, probably trying to figure out what those strange little things were that were falling out of the sky.  After receiving guidance to him I couldn’t believe I was actually able to not only resolve the dog at the distance, but after becoming accustomed to the image, I could actually tell which way he was facing as well.  After making some quick micrometer adjustments a couple more Sierras were airborne again, and I watched through the spotting scope as the bullets impacted surprisingly quite close to the prairie dog.  By this time the slight breeze of before had matured into a steady 10-15 m.p.h. crosswind, and the shooters both found themselves adjusting and readjusting elevation and windage micrometers as Sierras were impacting within a 10 ft. radius of the dog.  Finally after another 10 shots or so one of the bullets actually creased just left of his mound, and gave him enough of a scare to cause him to scurry off to another hole close by, into which, he promptly disappeared – all this at a distance of 2 miles.

           


Close-up of Bruce's Win. 70 action, and the base of Elmer Laitala's Super Long Range Scope Mount (SLRSM)

           Now I’ll freely admit that a few weeks ago when Kreg told me they were going for a 2 mile prairie dog my skepticism meter hit an all time high.  Although I had witnessed their attempts to break their own world records in the past, and was quite impressed with the ability of these guys and their guns to shoot accurately at the ranges they were trying for – I mean, come on – 2 miles??  After all, even with high-powered optics how could one even see a coke can sized critter at that range anyway?  Besides that, considering the average time of flight between their two guns (10 seconds) Mother Nature has an inordinate amount of time to manipulate the bullet’s windage and trajectory before it comes to – God only knows where.  Obviously their group size at 2 miles or 3520 yds. is idealistically 3.5X their average at 1000 (about 5”) which equates to approximately 18” or so at the target yardage.  Throw in all the variables, and we have to ask ourselves, can we even legitimize what’s occurring at that range by labeling it as a “group”?

           
           But all aside, I was there that day, and although the calculations may not agree, I can bear witness to the effectiveness of their system.  And now that I’ve seen it with my own eyes my skepticism has been dispelled, as I know without question that they will accomplish their goal soon enough.

           
           Obviously in order to turn this goal into reality Bruce and Kreg must depend upon, let’s say, a sort of skillful manipulation of luck, if you will.  If you’ve been following this “saga” through the pages of this magazine and its sister publications (all three previous articles are published in the PS book “Precision Shooting at 1,000 Yards” – Chapter 5 “Ultra Long Range Shooting In Colorado”) then you’ll recall that these guys aren’t just grabbing grampa’s old “thutty-thutty” off the mantelpiece, and pointing it


Close-up of Elmer's SLRSM with Leupold/Premier 20-50X conversion mounted.

skyward in a feeble attempt to lob-one-in on some such unfortunate rodent hoping to kill him via blunt trauma.  As mentioned in the previous articles Bruce has been avidly pursuing his interest for many years.  He has graduated through the various shooting disciplines, i.e.; archery, handguns, factory varmint-type rifles attempting to reach out farther and farther in range, culminating now in the .30 and .338 calibers with their corresponding high B.C. Sierra MK’s.  He and partner Kreg continue out to unheard of ranges using state-of-the-art equipment.  These guys aren’t the type to be bound by the conventional, as their unconventional goals dictate unconventional practices and procedures.

           
           After Kreg went beyond the 1.75 mile mark though, they both came to the realization that if they we going to continue farther in range they would have to reevaluate their equipment choices to incorporate some innovative ideas and designs.

           
           One problem they were frequently running into was the scope mounting system.  Although effective at the ranges they were shooting, the system lacked the flexibility necessary to make quick adjustment for shooting at various ranges during the same shooting session.  Coincidentally, a precision machinist by the name of Elmer Laitala of Harbor Engineering (
Ogilvie, MN) had just designed a highly efficient and specialized base and ring system that could be easily adjusted into the field for 100 to about 3000 yds.  Interested readers are advised to refer to the photo(s) of Elmer’s system as I attempt to explain its workings here.  His design incorporates a massive two-piece base system atop which sits a set of scope “yokes” fore and aft.  Two large scope rings are machined to slide into these yokes precisely, and are held tight by several precision
socket-head cap screws, and shoulder bolts.  These screws and bolts are alternately loosened and tightened whenever an elevation adjustment becomes necessary.  The aft yoke has a precision


Close-ups of Kreg's .338 LMAI showing big Rampro action, Elmer's SLRSM with Leupold/Premier 20-50X conversion, and Bruce's custom barrel bedding block.

slot machined into both sides through which the screws pass allowing the ocular part of the scope to be moved up or down as the objective end pivots in its mount.  A micrometer is mounted atop the rear yoke from which accurate adjustments can be made and recorded for various ranges.  Simply loosen the ocular and objective screws, adjust the micrometer to the proper setting for the prairie dog town XXXX yds. distant, then retighten the entire works.  Fine adjustments are made internally via scope turrets.

           
           Windage adjustments are made at the base which is actually a 2-piece system.  The lower portion is machined as a standard base normally would be, but is mated to the upper part by 2 pins.  These pins slide into their respective female counterparts in the upper base.  The forward counterpart is simply a machined hole into which the front pin is precisely mated.  The rear counterpart is, of course, another precisely machined curved slot which allows the upper part of the base to be moved right and/or left for windage using another micrometer as a reference and stop just like the elevation adjustment.  I’ve seen the system up close and personal, and believe me dear reader when I tell you that it is, simply put, an engineering wonder.

           
           Recently I spoke first hand with the designer himself about his system.  Elmer said he came up with the idea when he joined the Varmint Hunters Association.  The organization has established various “clubs” or categories based on your longest confirmed (by another member of the VHA) shot on a “varmint” species
(typically prairie dogs +/or woodchucks).  The categories are divided into 500 yd. increments, and every time you break into the 500, 1000, or maybe 1500 yd. range you get a membership in the club, and a pin as a reward.  When


Bruce prepares for a shot at 2 miles.

Elmer saw that Bruce and Kreg were the only members beyond 2000 yds. it fascinated him, and he knew he had to give it a go.  He purchased a Savage 112 BVSS in 300 Mag., and with a few modifications put himself in the 1000, and 1500 yd. clubs using standard factory rings and bases, with the Leupold/Premier 8.5X-25X boost to 20X-50X.  He quickly discovered that 1500 yds. was about the limit with the standard factory mounting systems, and internal adjustments on the Leupold.  With his background as a precision machinist, he initially considered going the same route as Bruce with a fixed custom elevated base, and Burris Posi-Align rings.  But as good as the system was he knew it lacked the flexibility for varying ranges.  He thought long and hard about it, and finally brainstormed his current long range base and ring system, with which he recently became a card-carrying member of the 2000 yd. Club himself.  He actually manufactures 2 different models.  His original design runs around $750, and has 200 minutes of elevation adjustment with no windage option.  This system works well out to around 3000 yds., but when Elmer met Bruce and Kreg he knew their needs would require a windage adjustment built in as well.  Once again, he thought long and hard, and brainstormed the windage modification described above.  This new package sells for a cool $1000, and includes an additional 600 minutes of elevation adjustment for a grand total of 800 minutes of elevation, and 200 of windage.  As Bruce explains Elmer’s design would take them from zero to app. 5000 yds. or about 3-3.5 miles, obviously depending upon the trajectory of the chosen cartridge/bullet combination.  Bruce says he’ll be attempting 3.5 miles as soon as Sierra comes out with their 20mm 2500 gr. “Super-Match-king (SMK)”.  Recently I contacted Sierra’s tech line to ask about the new bullet, and they responded with a most emphatic “huh”!!?

           
 


Kreg's big Rampro .338 Lapua Magnum Ackley Improved showing Elmer Laitala's SLRSM, and Bruce's custom barrel bedding block.

          Laitala’s whole system is marvelously designed, and can easily be returned to zero, as both Bruce and Kreg demonstrated to me that

day.  When finished shooting for the morning they returned their scopes and mounts to the preset 100 yd. zero’s, and nailed 2 cowpies about 150 yds. out.  Typically though Kreg and Bruce are within ½” of their 100 yd. zero’s after shooting at 2 miles, proving just how accurate Elmer’s system is – quite impressive to say the least.  The design is extremely innovative and could prove useful in many different types of long range applications. Elmer’s quite the engineer as well as precision machinist, and if you can think it up he can probably make it work.

           
           Bruce has just recently opened up his own shop in Pueblo West preferring to specialize in bench, varmint, and specialty-purpose big-game rifles and pistols.  While building his and Kreg’s new 2 mile prairie dog guns, Bruce decided to throw in a new innovation of his own design.  It’s actually sort of a new twist on an old idea which Bruce feels provides an improvement over current technology.  For years the 1000 yd. boys (and girls) have been shooting long heavy barrels that if left unsupported put considerable stress on the action. Most competitors are now having their guns built with some sort of support mechanism (barrel bedding block) in the barrel/action juncture to help with this stressful condition.  Most of these barrel blocks are bedded into the stock.  Bruce has taken the procedure a step further though by attaching a large aircraft-grade aluminum plate under the first 8” of the barrel, another in the bottom of the forearm, which attaches to a third and final plate that sits atop the action/barrel juncture.  The 3 plates are held together with 16 3/8ths X 24 machine screws, and 4 precision ground guide pins, sandwiching the entire works together tripledecker style, which makes for an extremely rigid and secure design.  I remember watching one day in his shop recently when he demonstrated how precise his barrel block system is.  As he assembled the unit, each consecutive piece slid down on the next, very slowly, as if on a cushion of air.  Since using this design


Kreg's gun on a bench in field showing big Rapro action, Elmer's SLRSM. Bruce's custom barrel bedding block, 36" Krieger barrel, and Elkridge's laminated bench stock.

Bruce has noticed quite an improvement in the accuracy of these heavy rifles which weigh in the neighborhood of 35-40 lbs.  Kreg’s big .338 is capable of putting 20% of its shots into a 36” gong at 2 miles – a testimony to the accuracy of Bruce’s system.

           
           Bruce has chosen to stick with the .308 Ackley Improved, as has been thoroughly discussed in previous articles, and has been more than satisfied with the 30 cal. barrels he has been receiving from Boots Obermeyer over the years.

           
           Kreg, on the other hand, has made a slight change in cartridge selection in that he chose to provide a little more velocity and energy to the 300 gr. .338 Sierra MK.  He decided to increase the case capacity of the .338 Lapua Magnum by blowing it out to Ackley’s Improved configuration.  But after chambering to the improved case Kreg had Elmer run the numbers across his Silhouette Ballistics Program, and they came up with some interesting conclusions.  The big variable in super long range shooting is time of flight, as the longer a projectile is in the air, the more time external forces have to alter its flight path.  So the sooner the bullet gets to the target range the better.  Obviously the higher the form factor and ballistic coefficient, the more retained velocity at any range, but the kickers here are the range to the target, and barrel life.  Kreg came to the realization that increasing powder charges will shorten the life of the barrel, especially when the target ranges are so far away that it may take more than a few rounds at each range to make a connection, not to mention all the preparatory shooting that’s involved, i.e. barrel conditioning, load development, etc.  As it turns out 2 mile flight time is insignificantly shortened by 100-200 f.p.s. more velocity, therefore, although Kreg is using a case that is capable of more horsepower, he chose to stick with his original load of 85 gr. IMR 7828 in the improved case.

           
           Kreg has also made some changes in his instrument of choice.  He elected to go the custom action route, and purchased a large Rampro for his Artus-built .338 Lapua Magnum Ackley Improved.  It’s bedded in a big laminated Elkridge bench stock, and has a 39” Krieger stainless barrel installed.

           


Close-up of Bruce's custom 3 piece barrel bedding block.

           Another problem they were running into was trying to find a gun case large enough to transport these rather oversize firearms, so they contracted Alan Marck of Marck’s Sheet Metal, Inc. also of Pueblo West to make some custom cases for them.  He fabricated 2 huge foam-lined cases that are both strong and durable at a reasonable price.

           
          
Bruce spent a lot of time on the phone discussing reamers with Dave Kiff @ Pacific Precision Tool and Gauge.  Both the .308 AI, and .338 LMAI reamers are from him.  They are a special match grade utilizing Dave’s parallel-throating system.  These special reamers guarantee precise bullet alignment, ensuring top accuracy without the extra pressure of jamming the bullet into the lands.  Dave believes there is no reason to manufacture these precision reamers at a high cost to the public, therefore his special reamers are the same price as the standard SAAMI’s he also produces.

           
           Bruce recently began using some of Greg Tannel’s (Gre-Tan Rifles, GTR) precision machining tools, specifically his Chambering Flushing System, and his special precision reamer holder.  Interested readers are advised to refer to an article published in PS issue 8/99 entitled “GTR Tooling’s Muzzle Flush Coolant System” in which author John Eckenrode thoroughly discusses the advantages of Greg’s use of a flood coolant system while cutting the chamber.  Since I am a shooter and writer, and not a gunsmith, all I can give here is a short layman’s description of his special precision reamer holder.  After wading through the technotalk of both Bruce and Greg, I gathered the system provides a hands-free floating holder that precisely self-aligns the reamer with


Big Rampro action.

the bore while cutting the hamber.  Interested readers are of course advised to speak to the man himself for specifics.  Another article was recently published on Greg’s action accurizing in PS issue 12/01 by Randolph Constantine, and I understand that Tannel’s innovative designs are regarded by many to be the wave of the future for precision gun builders.

           
            No doubt there are some out there that would like to know just what kind of trajectories we’re talking about here; myself included.  Recently, Elmer ran a drop chart for both Bruce and Kreg’s loads on his Silhouette Ballistics Program, (
Taylor, MI).  As for Bruce’s .308 AI,
the midrange trajectory for the 220 gr. Sierra @ 2400 f.p.s. m.v. is about 135 yds. above line of sight, and showed 365.6 m.o.a. of elevation required at 3520 yds. from a 100 yd. zero.  Remaining velocity and energy at the target yardage is 703 f.p.s., and 241 ft. lbs. respectively.  Using the same


Close-up of Elmer's SLRSM.

calculations Kreg’s .338” 300 gr. Sierra’s at 2750 f.p.s. m.v. are running 92 yds. above line of sight a the trajectories apex, and 245.4 m.o.a. of elevation require for 3520 yds.  The 300 gr. Sierra delivers 817 f.p.s. with 445 ft. lbs. remaining velocity and energy respectively at the target yardage.  Although the energy figures are quite low at two miles they are surprisingly higher than I had anticipated.

           
           Although Bruce and Kreg’s goal is considerably different than the thousand yard competitors, in either endeavor accuracy is paramount in importance, and I have often secretly wondered to myself just how well these guys would stack up to the long range paper punchers.  The end result of all this effort inevitably must be put to the test on the range before they could even begin to think about sending bullets downrange at the distances they are attempting.  Kreg’s barrel break-in

groups averaged .557” @ a hundred yds., for 15 3-shot groups, which includes cleaning between each group, and various powder combinations.  His aforementioned long range load is netting him an avg. of about 6” at a thousand.  Bruce is turning in similar groups as well.  Kreg intends to begin competing shortly at the various 1000 yd. matches with his new .338 LMAI.

           
          But first it’s 2 miles, and I for one, as a disinterested observer know that some morning, in the not-too-distant future, a pair of sleek Sierra HP Matchkings will speed their way through 2 miles of variable air currents toward their intended target.  A skillful manipulation of luck, or maybe a lucky manipulation of skill, depending upon your viewpoint, will allow one of those big Sierra’s to make history, as its flight path intersects with an unsuspecting prairie dog.  And what will they have accomplished for all their efforts?  That’s simply for them to know, and us to speculate.


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ADDRESSES:

1) Pacific Tool and Gauge. P.O. Box 2549, 598 Avenue C, White City, OR 97503. 541-826-5808.
2) Gré-Tan Rifles, 29742 W.C.R., 50 Kersey, CO 80644. 970-353-6176.
3) Marck's Sheet Metal, Inc., 621 E. Industrial Boulevard, Pueblo, CO 81007. 719-564-9238.
4) Harbor Engineering, 1729 Harbor Street, Ogilvie, MN 56358 320-272-4564.