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August 19th, 2014
Anschütz now has its own importation hub in the USA. This new facility, located in Trussville, Alabama, will operate as a direct extension of the parent company, J.G. ANSCHÜTZ GmbH & Co.KG of Germany. Having its own importation facility will help Anschütz supply rifles to the American market more efficiently. Steven Boelter, President of Anschütz North American (NA) operations, tells us that that the new Alabama facility will allow Anschütz to import a wider range of products and carry a larger standing inventory. That’s good for rimfire and air rifle customers.
The new importation/distribution center will soon be supported by an in-house Anschütz service center that will handle warranty repairs and custom upgrades. This will offer Anschütz after-sales service for all company products, as well as warranty support, repairs, spare parts, and tech info. (This new service center will operate as an adjunct to other existing target and air rifle service centers within the USA.) Learn more about the soon-to-be launched service center at www.anschutznorthamerica.com.
Anschütz NA does not sell directly to consumers, but if you are interested in a particular Anschütz product, you can contact the Anschütz’s staff in Alambama. They will answer your questions or connect you with a current Anschütz dealer. The established Anschütz distribution chain and main dealer network in the US will continue to operate as before.
Anschütz North America
www.anschutznorthamerica.com
7661 Commerce Lane
P.O. Box 129
Trussville, AL 35173-2837
Phone: 205-655-7500
August 19th, 2014
 In response to a Bulletin article about Protective Eyewear, one of our Canadian readers posted a personal story. His account demonstrates the importance of wearing eye protection whenever you shoot — no matter what type of firearm you are using — even air rifles. We hope all our readers take this to heart. All too often at rifle matches we see shooters, even some top competitors, risking their vision by failing to wear eye protection.
 Eye Protection — Lesson Learned
by Nicholas from Canada
As a boy on a mixed farm on the plains the first shooting stick I owned was a Red Ryder BB gun. My Dad bought it for me as I showed a keen interest in the shooting and hunting sports. I was about 9 years old at the time.
We had literally thousands of sparrows in our large farm yard and they liked to roost on the steel railings in the barn loft. I took to slowly thinning out their ranks by flashlight at night as these little winged pests settled in the farm buildings.
One evening as I slayed sparrow after sparrow in the barn loft — with about a dozen farm cats following me to consume these easy meals, I fired at another bird centered in my flashlight beam.
However, my aim was a bit low — and the copper pellet hit the steel beam square on. Instantly I felt a sharp pain as the BB bounced back and hit me squarely between the eyes on the bridge of my nose – drawing blood from the partial penetration into the skin. A half inch either way and I’d have lost an eye!
Never, never, never shoot at any target with a steel background with any firearm, even a BB gun – is the hard lesson I learned, and wear the best shooting glasses that money can buy!
PLEASE REMEMBER THAT!!
 Editor’s Comment: Among competitive pistol shooters, the use of safety eyewear is universal. You’ll never see Rob Leatham, Julie Golob, or Jerry Miculek competing without eye protection — for good reason. The handgun sports’ governing bodies effectively enforce mandatory eye protection policies. We wish the same could be said for competitive rifle shooting. We often see benchrest, High Power, and F-Class competitors shooting without eye protection. We’ve heard all the excuses, yet none of them trump the safety considerations involved.
We recommend that all shooters and hunters employ eye protection whenever they use firearms or are at a location where live fire is taking place. You only have two eyes. A tiny bullet fragment or ricochet is all it takes to cause permanent blindness in one or both eyes. As rifle shooters, we place our eyes a couple inches away from a combustion chamber operating at pressures up to 70,000 psi. I know quite a few guys who will religiously put on safety glasses when running a lathe or a drill press, yet the same guys won’t use eye protection when shooting their rifles — simply because it is “inconvenient”. That’s nuts. It doesn’t matter is you are a cub scout or a multi-time National Champion — you should wear eye protection.
Be wise — protect your eyes. To learn more about eyewear safety standards, and to learn about the latest options in ANSI Z87-certified protective eyewear, read our article on Eye Protection for Shooters.
August 16th, 2014
Can you form a wildcat cartridge such as the 6 Dasher without expending primer, powders, and bullets? Absolutely. Using the hydro-forming method you can form improved cases in your workshop with no firing whatsoever, so there is no wear on your precious barrel. Watch this video to see how it’s done:
6 Dasher Case Hydro-Forming Demonstration:
Forum member Wes J. (aka P1ZombieKiller) has produced a helpful video showing how to form Dasher cases use the Hornady Hydraulic forming die kit. This includes a two-part die (body and piston), and a special shell holder. To form the case, you insert a primer in your virgin brass, top the case off with with a fluid (water or alcohol), then run the case up into the Hydro-forming die. A few stout whacks with a hammer and your case is 95% formed.
 Hydro-Forming Procedure Step-by-Step:
1. Insert spent primer in new 6mmBR brass case.
2. Fill with water or alcohol (Wes prefers alcohol).
3. Wipe excess fluid off case.
4. Place case in special Hornady shell-holder (no primer hole).
5. Run case up into Hydraulic forming die.
6. Smack top piston of forming die 3-4 times with rubber mallet or dead-blow hammer.
7. Inspect case, re-fill and repeat if necessary.
8. Drain alcohol (or water) into container.
9. Remove primer (and save for re-use).
10. Blow-dry formed case. Inspect and measure formed case.
Wes achieves very uniform cartridge OALs with this method. He measured ten (10) hydro-formed 6 Dasher cases and got these results: two @ 1.536″; 2 @ 1.537″; and 6 @ 1.538″.
Three or Four Whacks Produces a 95%-Formed Case
With a Hornady hydro-forming die, hydraulic pressure does the job of blowing out the shoulders of your improved case. The process is relatively simple. Place a spent primer in the bottom of a new piece of brass. Fill the case with water, and then slip it into a special Hornady shell-holder with no hole in the middle. Then you run the case up into the forming die. Now comes the fun part. You gently insert a plunger (hydraulic ram) from the top, and give it three or four stiff whacks with a mallet (or better yet, a dead-blow hammer). Remove the plunger and you have a 95% formed case, ready to load.
 Hornady supplies a shell holder made specifically for the hydro die; there’s no hole in the bottom of it. Just insert a spent primer into the primer pocket and you’re ready to go. The spent primer combined with the solid shell holder, keeps the water from seeping out of the primer pocket. The primer pushes out a little bit during this process, but it’s impossible for it to come out because of the way the shell holder is designed. The shell holder has a grove which allows the case to slide out of the shell holder even when the primer protrudes a bit.
Story tip from Body Allen. We welcome reader submissions.
July 21st, 2014
Muzzle brakes are controversial. Some people swear by them, while others swear at them. Still, there’s no question that a good brake can reduce felt recoil up to 45%. And likewise, the best brakes, when installed properly, seem to have no negative effect on accuracy.
Roy Bertalotto has done considerable experimentation with muzzle brakes, testing dozens of brake designs on his own rifles over the past few years. Roy’s article, Adventures with Muzzle Brakes, discusses various aspects of muzzle brake design and performance. Roy doesn’t claim that his testing is definitive, but his article is definitely worth a read. Here are some of Roy’s interesting findings:
Exit Hole Diameter
“Best accuracy and effectiveness of the brake was obtained with a hole .020″ over bullet diameter. If the exit hole is too small, such as +.005″ over bullet diameter, accuracy suffers. If the depth of the exit hole is too shallow, the metal around the hole will erode very quickly.”
Hole Placement
“The most effective braking was with a brake 1″ in diameter with a 3/4″ exit hole on each side, just in front of the muzzle. The bullet passes through a cone of 35 degrees before it exits the brake. (Like the tank example), Incredible reduction of recoil. But loud and ugly. Very easy to make since you don’t need a spin fixture or a dividing head.”
Bottom Gas Venting Helps Accuracy
“In my tests, not having holes all around the brake effects accuracy a bit. I believe it does something to the bullet by the air pushed ahead of the bullet creating unequal turbulence in the bullet path. I’ve tried a few brakes where I drilled only holes on the top, test fired, and then completed holes on the bottom and in every case, accuracy improved.” Below are spiral-ported brakes crafted by Clay Spencer.
Brakes Work Best with High-Pressure Cartridges
“The higher the pressure of the particular round, the more effective the brake. I have over 20 rifles with brakes. The 220 Swift is the king of reduction. Followed very closely by the 25-06, 6mm Remington, any Weatherby small bore. With a proper brake and a hot handload under a 40 gr bullet, the Swift will move 1/2″ to the rear and 0 muzzle rise! Big boomers with low pressure like 45-70s and shot guns benefit the least.” [Editor’s Note: Roy is judging effectiveness by the percentage of recoil reduction rather than absolute levels of recoil. Obviously if you start with a heavier-recoiling round, the absolute amount of recoil energy reduction is greater. Roy is really talking about efficiency–brakes are most efficient when used with high-pressure cartridges.]
Installation is Key to Accuracy
Roy’s findings are fascinating and suggest that further study of muzzle brakes is warranted. But we can all agree that precision installation of the brake is essential for accuracy. A poorly-installed, mis-aligned brake will degrade accuracy, that is well-known.
Harrell’s Precision has made thousands of muzzle brakes, in many styles and port arrangements. The Harrell brothers offer some good advice for gunsmiths installing brakes: “Muzzle brakes aren’t magic, they reduce recoil by redirecting exiting gas. What’s important is that they are straight and the threads are perpendicular with the base. The only way to get the base and threads perpendicular is to thread, not tap, them on a lathe.”
July 9th, 2014
Commentary by Robert Whitley
In recent years several major firearms component suppliers have promoted the idea of the “do-it-yourself” AR-15 build up. In one sense this is a good thing because it promotes peoples’ education and understanding of firearms, but the down side of this is some folks are assembling and modifying AR-15s without an understanding of the rifle and without the necessary skills and tools to do things properly. The net result of this “do-it-yourself” work can be an AR-15 that is non-functional, problematic or dangerous. Here are two examples of common issues with “do-it-yourself” modifications.
Opening Up the Ejection Port
One common modification for AR-15’s is the opening up of the ejection port. This is typically done to permit more room for ejection or loading of the rifle, and it is also typically done in conjunction with a side charging handle modification.
A common issue I have seen with this modification is that the person opening up the port removes the upper right hand carrier support and riding surface. The net result of this is that the carrier sits loose in the upper receiver when the bolt is in lock-up and this can have very detrimental effects on the function and accuracy of the AR-15. Below are more pictures of one that I saw recently.
Click Arrows to See all FOUR Pictures
 CaptionUpper Receiver Harmed by Modification  CaptionReceiver Showing Gas Key Hits Wrong Buffer Installed
Another common mistake is the use of an improper buffer with the rifle (i.e. like using a carbine buffer in a standard rifle length buffer tube). There are many after market buffers being sold out there, but if the wrong buffer is used with the rifle, it can allow the bolt carrier to cycle too far back so that the rear of the carrier gas key becomes the stop for the carrier (i.e. when it smashes into the upper part of the lower receiver – OUCH!).
We have even seen situations where the gas key is snapped right off the carrier from this, and it completely disables the rifle and can also cause extensive damage to the firearm as well. Unfortunately we have seen this situation far too often and it is clear that a person needs to fully understand how the buffer assembly works if “do-it-yourself” work is going to be done to the buffer assembly, since everything done to the buffer assembly has an effect on the rifle, its function and accuracy.
While I applaud the person who is self-reliant and has a “can do” attitude, the other side of this is when it comes to a firearm, “do-it-yourself” work should only be done when and if one fully understands the rifle and how it functions and how the work will affect the rifle.
Robert Whitley
AR-X Enterprises, LLC
199 North Broad Street
Doylestown, PA 18901
(215) 348-8789
www.6mmAR.com
July 2nd, 2014
 Want to shoot better scores at your next match? Here’s a smart, inexpensive do-it-yourself project from the good folks at Criterion Barrels. For less than one dollar in materials, in just a few minutes you can create a handy, effective mirage shield, custom-fitted to your favorite rifle.
All precision shooters should be familiar with mirage, a form of optical distortion caused primarily by variations in air temperature. Savvy shooters will use mirage as a valuable tool when gauging wind speed and direction. Natural mirage is unavoidable, but there are many techniques designed to limit its influence in long-range marksmanship.
A form of mirage can be produced by the barrel itself. Heat rising from the barrel may distort sight picture through your optics, leading to erratic results. Mirage caused by barrel heat can be reduced dramatically by a simple, light-weight mirage shield.
How to Make a Mirage Shield
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A mirage shield is an extremely cost-effective way to eliminate a commonly-encountered problem. Making your own mirage shield is easy. Using old venetian blind strips and common household materials and tools, you can construct your own mirage shield for under one dollar. |
Materials Required:
1. Vertical PVC Venetian blind panel
2. Three 1”x1” pieces adhesive-backed Velcro
3. Ruler or tape measure
4. Scissors or box cutter
5. Pencil or marker |
1. Measure the distance from the end of the receiver or rail to the crown of the barrel.
2. Using a pencil and ruler, measure the same distance and mark an even line across the blind.
3. Cut across the line using scissors or a box cutter, shortening the blind to the required length. (Remember, measure twice, cut once!)
4. Expose the adhesive backing on the loop side of the Velcro. Center and apply the Velcro strips on the barrel at regular intervals.
5. Expose the adhesive backing of the fuzzy side of the Velcro.
6. Place the blind on the upper side of the barrel. Apply downward pressure. Once the Velcro has secured itself to the barrel, separate the two sides. Proceed to mold both sides of the Velcro to fit the contour of their respective surfaces.
7. Reaffix the blind. Barrel related mirage is now a thing of the past!
How to Remove and Re-Attach the Mirage Shield
Removal of your mirage shield is accomplished by simply removing the blind. You can un-install the Velcro by pulling off the strips and then gently removing any adhesive residue left behind using an appropriate solvent. (Simple cooking oil may do the job.) Caution: With fine, high-polish blued barrels, test any solvent on a non-visible section of the barrel. Before storing the gun, re-oil the barrel to remove active solvents and residual fingerprints.
July 1st, 2014
 A while back, Sinclair International’s Reloading Press Blog featured a “round-table” discussion of reloading techniques. Sinclair’s team of tech staffers were asked: “What do you feel is the one-most crucial step in precision reloading?”
Here are their responses (along with comments from our Editors):
Phil Hoham: “I feel that when working up a load do not go too high or too low in your powder charge. Stay away from “suggested loads” you hear at the range, or on the internet. Always be sure to use a published reloading manual that presents not only minimums and maximums, but also pressure, velocity, and a proper range of powders used. Do not get distracted in the reloading process, and remain focused at all times during each step involved.”
AccurateShooter.com: Some loads presented on the Internet are OK as a starting point, but it is absolutely critical to understand that pressure maximums will vary considerably from one rifle to another (of the same chambering). For example, one 6mmBR rifle shooting 105gr bullets can max out with 30.0 grains of Varget powder, while another rifle, with the same chamber dimensions, but a different barrel, could tolerate (and perform better) with half a grain more powder. You need to adjust recommended loads to your particular rifle and barrel.
Pete Petros: “This could be a very broad topic, but if I were to pick one, it would be making sure to pay close attention, and weigh each and every powder charge to ensure that each load is exact and consistent. This is important not only for accuracy, but also for safety reasons.”
AccurateShooter.com: If you’re shooting beyond 200 yards, it is critical to weigh your loads with an accurate scale. Loads that are uniform (within a few kernels) will exhibit lower Extreme Spread and Standard Deviation. And remember, even if you stick with the same powder, when you get a new powder lot, you may have to adjust your load quite a bit. For example, .308 Palma shooters have learned they may need to adjust Varget loads by up to a full grain from one lot of Varget to the next.
Ron Dague: “I feel that the most important step(s) in reloading for accuracy are in the initial case prep. Uniforming the primer pocket to the same depth to ensure consistency in primer seating is a crucial step. Additionally de-burring the flash holes, each in the same way to clean up and chamfer the inside is important. It ensures that the ignition from the primer is uniform and flows out in the same consistent pattern. Doing so will create uniform powder ignition and tighten up your velocity Extreme Spread.”
AccurateShooter.com: With some brands of brass, primer pocket uniforming and flash-hole deburring is useful. However, with the best Lapua, Norma, and RWS brass it may be unnecessary, or worse, counter-productive. So long as your Lapua brass flash-holes are not obstructed or smaller than spec, it may be best to leave them alone. This is particularly true with the small flash holes in 220 Russian, 6BR, and 6.5×47 cases. MOST of the flash-hole reaming tools on the market have cutting bits that vary in size because of manufacturing tolerances. We’ve found tools with an advertised diameter of .0625″ (1/16″) that actually cut an 0.068″ hole. In addition, we are wary of flash-hole deburring tools that cut an aggressive inside chamfer on the flash-holes. The reason is that it is very difficult to control the amount of chamfer precisely, even with tools that have a depth stop.
Rod Green: “I feel that bullet seating is the most important step. If you had focused on making sure all prior steps (case prep, powder charge, etc.) of the process have been carefully taken to ensure uniformity, bullet seating is the last step, and can mean all the difference in the world in terms of consistency. Making sure that the bullet is seated to the same depth each time, and time is taken to ensure that true aligned seating can make the load.”
Bob Blaine: “I agree with Rod. I strongly feel that consistent bullet seating depth is the most important step in creating the most accurate hand loads. I have seen the results in both my bench and long range rifles. Taking the time to ensure exactness in the seating process is by far, the number one most important step in my book.”
AccurateShooter.com: Agreed. When loading match ammo, after bullet seating, we check every loaded round for base of case to ogive length. If it varies by more than 3 thousandths, that round is segregated or we attempt to re-seat the bullet. We measure base of case to bullet ogive with a comparator mounted on one jaw of our calipers. You may have to pre-sort your bullets to hold the case-base to ogive measurement (of loaded rounds) within .003″.
June 1st, 2014
When we first ran this story a while back, it generated great interest among readers. By popular request, we’re reprinting this story, in case you missed it the first time around. — Editor
 Precision shooters favor premium brass from Lapua, Norma, or RWS. (Lake City also makes quality brass in military calibers.) Premium brass delivers better accuracy, more consistent velocities, and longer life. Shooters understand the importance of good brass, but many of us have no idea how cartridge cases are actually made. Here’s how it’s done.
The process starts with a brass disk stamped from strips of metal. Then, through a series of stages, the brass is extruded or drawn into a cylindrical shape. In the extrusion process the brass is squeezed through a die under tremendous pressure. This is repeated two or three times typically. In the more traditional “draw” process, the case is progressively stretched longer, in 3 to 5 stages, using a series of high-pressure rams forcing the brass into a form die. While extrusion may be more common today, RWS, which makes some of the most uniform brass in the world, still uses the draw process: “It starts with cup drawing after the bands have been punched out. RWS cases are drawn in three ‘stages’ and after each draw they are annealed, pickled, rinsed and subjected to further quality improvement measures. This achieves specific hardening of the brass cases and increases their resistance to extraordinary stresses.” FYI, Lapua also uses a traditional draw process to manufacture most of its cartridge brass (although Lapua employs some proprietary steps that are different from RWS’s methods).
Deep-Draw Ram Illustration from Demsey Mfg.
After the cases are extruded or drawn to max length, the cases are trimmed and the neck/shoulder are formed. Then the extractor groove (on rimless cases) is formed or machined, and the primer pocket is created in the base. One way to form the primer pocket is to use a hardened steel plug called a “bunter”. In the photos below you see the stages for forming a 20mm cannon case (courtesy OldAmmo.com), along with bunters used for Lake City rifle brass. This illustrates the draw process (as opposed to extrusion). The process of draw-forming rifle brass is that same as for this 20mm shell, just on a smaller scale.
River Valley Ordnance explains: “When a case is being made, it is drawn to its final draw length, with the diameter being slightly smaller than needed. At this point in its life, the head of the draw is slightly rounded, and there are no provisions for a primer. So the final drawn cases are trimmed to length, then run into the head bunter. A punch, ground to the intended contours for the inside of the case, pushes the draw into a cylindrical die and holds it in place while another punch rams into the case from the other end, mashing the bottom flat. That secondary ram holds the headstamp bunter punch.
The headstamp bunter punch has a protrusion on the end to make the primer pocket, and has raised lettering around the face to form the headstamp writing. This is, of course, all a mirror image of the finished case head. Small cases, such as 5.56×45, can be headed with a single strike. Larger cases, like 7.62×51 and 50 BMG, need to be struck once to form a dent for the primer pocket, then a second strike to finish the pocket, flatten the head, and imprint the writing. This second strike works the brass to harden it so it will support the pressure of firing.”
Thanks to Guy Hildebrand, of the Cartridge Collectors’ Exchange, OldAmmo.com, for providing this 20mm Draw Set photo. Bunter photo from River Valley Ordnance.
May 30th, 2014
See Results of Anti-Corrosion Product Test in Video
YouTube Link: http://youtu.be/uOB5eCReAQY
What anti-corrosion products really fight rust effectively? You’ll hear many opinions, but what do actual field tests reveal? One rifle shooter, who posts on YouTube as BlueonGoldZ, wanted to separate myth (and marketing claims) from reality, so he completed his own long-term rust test using metal samples. First he used ordinary tap water spray, and then he did a second, longer-duration test with a salt-spray solution. Nine different products were tested: Break Free CLP, Corrosion-X, Frog Lube, M-Pro 7, Outers, Pro-Shot Zero Friction, Rem Oil, Slip 2000, and Tetra Gun Triple Action CLP.
BlueonGoldZ initially examined each product for its “beading” properties with a normal tap water spray. But the main test involved many multiple weeks of exposure after a “dense” salt-water spray. (No rust formed after two weeks tap water exposure, so the test was accelerated with salt-water exposure).
The clear winners in the test, as shown by the screen shot above, were Corrosion-X (Best), and Frog-Lube (Second Best). The photo shows the test samples two weeks after being sprayed with salt water. The results are pretty dramatic — you can see with your own eyes what happened. We think this is a very useful bit of real-world research.
Results from Similar Long-Term Salt Exposure Test
Unfortunately, BlueonGoldZ’s test did NOT include Eezox, which we have found to be extremely effective (on a par with Corrosion-X). In another long-term test of corrosion preventatives, the two best rust fighters were Eezox and Corrosion-X in that order. Since that test was completed, Corrosion-X, already an excellent product, has been enhanced. CLICK HERE for Long-Term Salt Exposure Test Report.
May 28th, 2014
 While attending the CA Long Range Championship a while back, we had the opportunity to test the performance of a high-magnification (63X) spotting scope in near-ideal conditions (maybe the best I’ve ever witnessed). On the event’s last day we arrived at 5:45 am, literally as the sun was cresting the horizon. I quickly deployed our Pentax PF-100ED spotting scope, fitted with a Pentax SMC-XW 10mm fixed-power eyepiece. When used with the 100mm Pentax scope, this 10mm eyepiece yields 63X magnification. Befitting its $359.00 price, this eyepiece is extremely clear and sharp.
At the crack of dawn, viewing conditions were ideal. No mist, no mirage, no wind. The first thing this Editor noticed was that I could see metal nail heads on the target boards. That was astonishing. As soon as the first practice targets went up, to my surprise, I could see 6.5mm, 7mm, and 30-caliber bullet holes in the white at 1000 yards.
That’s right, I could see bullet holes at 1000. I know many of you folks may not believe that, but there was no mistaking when I saw a 7mm bullet cut the white line separating the Nine Ring and Eight Ring on the target in view. (I was watching that target as the shot was fired and saw the shot-hole form). And when I looked at the 30-cal targets, the bullet holes in the white were quite visible. In these perfect conditions I could also make out 3/8″ bolt heads on the target frames.
The Human Factor
When viewing the bullet holes, I was using my left naked eye (no safety glasses or magnification). I also had a contact lens in my right eye (needed for distance vision). To my surprise, while I could see the bullet holes without much difficulty with my left eye, things were fuzzier and slightly more blurry with the right eye, even when I re-focused the scope.
 Then I invited 3 or 4 shooters to look through the scope. One younger guy, with good eyes, said immediately: “Yeah, I can see the holes — right there at 4 o’clock and seven o’clock. Wow.” Some older guys, who were wearing glasses, could not see the holes at all, no matter what we did to the scope’s main focus and diopter adjustment.
The lesson here — if you have to wear glasses or corrective contact lenses, just that extra bit of optical interference may make a difference in what you can see through the scope. Basically anything that goes between the scope eyepiece and your eyeball can degrade the image somewhat. So… you may be better off removing your glasses if you can still obtain good focus sharpness using the diopter adjustment and focus ring. I did the left vs. right eye test a half dozen times, and I could definitely see small features at 1000 yards with my naked eye that I could not see with my right eye fitted with a contact lens. (I did have to re-focus the scope for each eye, since one had a corrective lens while the other did not.)
Mirage Degrades Image Sharpness and Resolution
The “magic light” prevailed for only an hour or so, and then we started to get some mirage. As soon as the mirage appeared I was no longer able to see raw bullet holes, though I could still easily see black pasters on the black bulls. When the mirage started, the sharpness of the visible image degraded a huge amount. Where I could see bullet holes at dawn, by mid-morning I could barely read the numbers on the scoring rings. Lesson: If you want to test the ulimate resolution of your optics, you need perfect conditions.
 Chromatic Aberration Revealed
As the light got brighter and the mirage increased I started to see blue and red fringing at the edges of the spotting disk and the large numerals. This was quite noticeable. On one side of the bright, white spotting disc you could see a dark red edge, while on the other side there was a blue edge (harder to see but still present).
The photo below was taken through the Pentax spotter lens using a point and shoot camera held up to the eyepiece. The sharpness of the Pentax was actually much better than this photo shows, but the through-the-lens image does clearly reveal the red and blue fringing. This fringing is caused by chromatic aberration — the failure of a lens to focus all colors to the same point. Chromatic aberration, most visible at high magnification, causes different wavelengths of light to have differing focal lengths (see diagram). Chromatic aberration manifests itself as “fringes” of color along boundaries that separate dark and bright parts of the image, because each color in the optical spectrum cannot be focused at a single common point on the optical axis. Keep in mind that the Pentax does have “ED” or low-dispersion glass, so the effect would be even more dramatic with a cheaper spotting scope.
If you wonder why top-of-the-line spotting scopes (such as the $3900 Leica APO-Televid 82) cost so much, the answer is that they will deliver even LESS chromatic aberration at long range and high magnification. With their exotic apochromatic (APO), ultra-low-dispersion glass, a few ultra-high-end spotting scopes can deliver an image without the color edging you see in the photo above.
The Pentax PF-100ED is a heck of a spotting scope. Any scope that can resolve bullet holes at 1000 yards is impressive. But if you want the ultimate in optical performance, with minimal chromatic aberration, you may need to step up to something like the 88mm Kowa Prominar TSN-883 with Flourite Crystal lenses ($2450.00 body only), or the 82mm Leica APO ($3899.00 with 25-50X eyepiece).
EDITOR’s NOTE: The purpose of this report is to show what is possible… in IDEAL conditions. With this Pentax 100mm, as well as a Swarovski 80mm, we have often been able to resolve 6mm bullet holes at 600 yards. But again, that performance requires really good viewing conditions. By 10:00 am at my range, even with the 100mm Pentax at 75 power, seeing 6mm bullet holes is “iffy” at best. So don’t go out and mortgage the house to buy a $4000 optic with the hope that you’ll be able to spot your shots at 1000 yards. If conditions are anything less than perfect, you’ll be lucky to see bullet holes at 500 yards. The real solution for very long-range spotting is to set up a remote target cam that broadcasts a video picture to a screen at your shooting station.
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