The experience and knowledge I have gained have substantially extended my personal comfort level. I am now confident that I can quickly establish precise holdover, eliminating any guesswork, and place a shot precisely in a big game animal’s vitals out to 650 yards. I’m satisfied with that. It is double the distance I felt comfortable with before I invested in top-of-the-line equipment and took the time to learn how to use it properly.

LIDT in energy density vs. pulse length and spot size. For short pulses, energy density becomes a constant with spot size. This graph was obtained from [1].

Fortunately, in recent years some of the most renowned bullet companies, whose products are favored by long-range competition shooters, have invested a great deal of time, money and research into building projectiles that combine extreme-range stability with the penetration, energy transfer and controlled expansion essential to a hunting bullet. They are expensive, but they are also expensive to make.

F-number

In this humble series we’ve looked at the tools and technology necessary to shoot effectively at long distances. We’ve touched upon the ethics of long-range hunting, a topic that has, and continues, to be flogged at length in the hunting media. There are proponents and opponents, and there is little I can, or choose, to add to the controversy surround that topic.

Please note that we have a buffer built in between the specified damage thresholds online and the tests which we have done, which accommodates variation between batches. Upon request, we can provide individual test information and a testing certificate. Contact Tech Support for more information.

Pulsed Nanosecond Laser Example: Scaling for Different WavelengthsSuppose that a pulsed laser system emits 10 ns pulses at 2.5 Hz, each with 100 mJ of energy at 1064 nm in a 16 mm diameter beam (1/e2) that must be attenuated with a neutral density filter. For a Gaussian output, these specifications result in a maximum energy density of 0.1 J/cm2. The damage threshold of an NDUV10A Ø25 mm, OD 1.0, reflective neutral density filter is 0.05 J/cm2 for 10 ns pulses at 355 nm, while the damage threshold of the similar NE10A absorptive filter is 10 J/cm2 for 10 ns pulses at 532 nm. As described on the previous tab, the LIDT value of an optic scales with the square root of the wavelength in the nanosecond pulse regime:

A dedicated rifleman (or woman) who knows he can place a shot accurately at 800 yards is infinitely more ethical than the amateur who is wishing and hoping at 300.

What I don’t have, if I am honest with myself, is the time, and frankly, the inclination, to invest hours upon hours and hundreds if not thousands of rounds in becoming a consistent 1000-yard shooter. There are no short cuts, regardless of what advertising claims may promise you. I enjoy playing the guitar, too, but the only way I’d ever be confused with Eric Clapton is if I went back 30 years, quit my job, and spent every waking moment playing the thing until my fingers bled, and then pushed myself to play even more. A rifle and a guitar do have one thing in common: pick one up only once every couple of months, and you’re never going to be that good.

Optical Density and TransmissionOptical density (OD) indicates the attenuation factor provided by an optical filter, i.e. how much it reduces the optical power of an incident beam. OD is related to the transmission, T, by the equation

I have not returned to the 1000-yard range yet, but I have several boxes of shiny new handloads that I intend to try as soon as I get a chance, and I am hoping that they will reduce my groups from broad-side-of-a-barn to something that might be covered with a yardstick.

Convincing someone they must drop that kind of money for a black tube with glass on both ends is a difficult sell. There is nothing inherently sexy about a scope. Rifles, though, are something different. They can be works of art, with beautifully patterned wood, deep, rich bluing, maybe even a touch of the engraver’s skill for those with substantial budgets. We caress them, clean them, some guys I know even talk to them. When a hunter finishes dropping a healthy chunk of his income on a rifle, convincing him he must do the same for a riflescope and mounts is a challenge. The temptation is to put as much as possible into a rifle, and save some money by settling for a lesser scope. Don’t do it.

The specifications to the right are measured data for Thorlabs' reflective neutral density filters. Damage threshold specifications are constant for a given optical density coating, regardless of the size of the filter.

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The energy density of the beam can be compared to the LIDT values of 1 J/cm2 and 3.5 J/cm2 for a BB1-E01 broadband dielectric mirror and an NB1-K08 Nd:YAG laser line mirror, respectively. Both of these LIDT values, while measured at 355 nm, were determined with a 10 ns pulsed laser at 10 Hz. Therefore, an adjustment must be applied for the shorter pulse duration of the system under consideration. As described on the previous tab, LIDT values in the nanosecond pulse regime scale with the square root of the laser pulse duration:

Optical filter

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The author had the right rifle and the right riflescope for 1000-yard shooting, but the wrong bullets. At least, that is the excuse today.

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So what did I learn from my 1000-yard adventure? As Clint Eastwood’s Dirty Harry character famously said, “A man has to know his limitations.” I have an excellent rifle, one of the best long-range riflescopes money can buy, the finest mounts, and now, bullets proven to provide quality and consistency while traveling well over a half mile.

So, it was back to the reloading bench, the only comfort being that perhaps it wasn’t my ability that was lacking, and I could blame the bullets.  It sounded good, anyway.

My friend Jerry had done just that, equipping his .300 Win Mag with a Nightforce NXS 3.5-15 x 50. It was a revelation to him after using a low-end scope for years. “I see things now I never saw before,” he said. Bingo. Step one accomplished.

This is what targets 1000 yards away look like. Shooting effectively at this distance poses a whole new set of challenges to the hunter and to his equipment.

His credentials as a mountain hunter include two ibex, bighorn and Dall sheep, a mountain goat, tahr, chamois, mouflon, and many timberline elk and mule deer. He lives at nearly 9000 feet in the Colorado Rockies, where, he says, “even looking for my car keys is a mountain hunt.”

In the first two installments of “How far is too far,” we’ve taken a rambling, roundabout journey in an attempt to answer the question posed by my friend Jerry just before a hunt. We expected that our hunt might require shooting at some extended distances, something with which Jerry had not had a lot of experience. He was comfortable to maybe 300 yards or so, but was rightly concerned about shooting at a living creature much beyond that. He did not want to wound a fine game animal, and I admired him for that. Far too often I’ve seen or heard hunters lobbing round after round at a distant elk or deer hoping to hit the hapless creature somewhere — anywhere. That is, in my opinion, beneath contempt.

[1] R. M. Wood, Optics and Laser Tech. 29, 517 (1998).[2] Roger M. Wood, Laser-Induced Damage of Optical Materials (Institute of Physics Publishing, Philadelphia, PA, 2003).[3] C. W. Carr et al., Phys. Rev. Lett. 91, 127402 (2003).[4] N. Bloembergen, Appl. Opt. 12, 661 (1973).

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That is only step one, though. While I pondered how to answer his question, I thought back to my first experience shooting at 1000 yards. I live about three hours from the NRA’s superb Whittington Center in New Mexico, and a couple of years back I had made a pilgrimage there for my first encounter with a 1000-yard range. I arrived brimming with confidence, with the same Nightforce scope Jerry had but mounted on a Sako .25-06 I’d owned for many years. The rifle was exceptionally accurate and consistent, capable of ¼ inch groups at 100 yards, and I had shot a lot of game with it. Nothing much beyond 300 yards, but I figured, if it is that good at 300 yards it must be equally good at 1000.

An AC127-030-C achromatic doublet lens has a specified CW LIDT of 350 W/cm, as tested at 1550 nm. CW damage threshold values typically scale directly with the wavelength of the laser source, so this yields an adjusted LIDT value:

where T is a value between 0 and 1. Choosing an ND filter with a higher optical density will translate to lower transmission and greater absorption of the incident light. For higher transmission and less absorption, a lower optical density would be appropriate. As an example, if a filter with an OD of 2 results in a transmission value of 0.01, this means the filter attenuates the beam to 1% of the incident power. Please note that the transmission data for our neutral density filters is provided in percent (%).

The pulse length must now be compensated for. The longer the pulse duration, the more energy the optic can handle. For pulse widths between 1 - 100 ns, an approximation is as follows:

Now compare the maximum energy density to that which is specified as the LIDT for the optic. If the optic was tested at a wavelength other than your operating wavelength, the damage threshold must be scaled appropriately [3]. A good rule of thumb is that the damage threshold has an inverse square root relationship with wavelength such that as you move to shorter wavelengths, the damage threshold decreases (i.e., a LIDT of 1 J/cm2 at 1064 nm scales to 0.7 J/cm2 at 532 nm):

In 2010, Matthew Kline broke the three-inch barrier for the first time with a new 1000 yard 10-shot Heavy Gun World Record. This is his record-shattering group of 2.815 inches, shown actual size. He used a .300 WSM and Nightforce 8-32 x 56 Precision Benchrest scope for this impressive shooting.

Od nd filter

The NRA Whittington Center, near Raton, New Mexico, is one of the finest shooting facilities in the nation. You can test your rifle shooting prowess from 100 to 1000 yards, and every distance in between.

Thorlabs' LIDT testing is done in compliance with ISO/DIS 11254 and ISO 21254 specifications.First, a low-power/energy beam is directed to the optic under test. The optic is exposed in 10 locations to this laser beam for 30 seconds (CW) or for a number of pulses (pulse repetition frequency specified). After exposure, the optic is examined by a microscope (~100X magnification) for any visible damage. The number of locations that are damaged at a particular power/energy level is recorded. Next, the power/energy is either increased or decreased and the optic is exposed at 10 new locations. This process is repeated until damage is observed. The damage threshold is then assigned to be the highest power/energy that the optic can withstand without causing damage. A histogram such as that below represents the testing of one BB1-E02 mirror.

LIDT in linear power density vs. pulse length and spot size. For long pulses to CW, linear power density becomes a constant with spot size. This graph was obtained from [1].

Pulsed lasers with high pulse repetition frequencies (PRF) may behave similarly to CW beams. Unfortunately, this is highly dependent on factors such as absorption and thermal diffusivity, so there is no reliable method for determining when a high PRF laser will damage an optic due to thermal effects. For beams with a high PRF both the average and peak powers must be compared to the equivalent CW power. Additionally, for highly transparent materials, there is little to no drop in the LIDT with increasing PRF.

While this rule of thumb provides a general trend, it is not a quantitative analysis of LIDT vs wavelength. In CW applications, for instance, damage scales more strongly with absorption in the coating and substrate, which does not necessarily scale well with wavelength. While the above procedure provides a good rule of thumb for LIDT values, please contact Tech Support if your wavelength is different from the specified LIDT wavelength. If your power density is less than the adjusted LIDT of the optic, then the optic should work for your application.

Beam diameter is also important to know when comparing damage thresholds. While the LIDT, when expressed in units of J/cm², scales independently of spot size; large beam sizes are more likely to illuminate a larger number of defects which can lead to greater variances in the LIDT [4]. For data presented here, a <1 mm beam size was used to measure the LIDT. For beams sizes greater than 5 mm, the LIDT (J/cm2) will not scale independently of beam diameter due to the larger size beam exposing more defects.

Almost any off-the-shelf modern rifle is capable of excellent accuracy, certainly one-MOA groups at 100 yards. A bit of fine-tuning with different loads and bullets can further shrink those groups. Conversely, the finest custom rifle will only shoot as well as the optics mounted upon it allow.

Tom Bulloch has worked in the optics industry for over 21 years. He has hunted on six continents, doing, as he puts it, “more hunting for less money than any man alive.”

Pulsed Nanosecond Laser Example: Scaling for Different Pulse DurationsSuppose that a pulsed Nd:YAG laser system is frequency tripled to produce a 10 Hz output, consisting of 2 ns output pulses at 355 nm, each with 1 J of energy, in a Gaussian beam with a 1.9 cm beam diameter (1/e2). The average energy density of each pulse is found by dividing the pulse energy by the beam area:

In order to illustrate the process of determining whether a given laser system will damage an optic, a number of example calculations of laser induced damage threshold are given below. For assistance with performing similar calculations, we provide a spreadsheet calculator that can be downloaded by clicking the button to the right. To use the calculator, enter the specified LIDT value of the optic under consideration and the relevant parameters of your laser system in the green boxes. The spreadsheet will then calculate a linear power density for CW and pulsed systems, as well as an energy density value for pulsed systems. These values are used to calculate adjusted, scaled LIDT values for the optics based on accepted scaling laws. This calculator assumes a Gaussian beam profile, so a correction factor must be introduced for other beam shapes (uniform, etc.). The LIDT scaling laws are determined from empirical relationships; their accuracy is not guaranteed. Remember that absorption by optics or coatings can significantly reduce LIDT in some spectral regions. These LIDT values are not valid for ultrashort pulses less than one nanosecond in duration.

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Precise shooting at extended ranges is almost impossible without a specialized reticle designed for the job. The Nightforce MOAR™ shown here is based on minute-of-angle principles, one minute of angle being 1.047 inches at 100 yards. Each vertical and horizontal marking on the MOAR represents one MOA. Minutes of angle are an angular unit of measurement, one MOA being 2.094 inches at 200 yards, 3.141 inches at 300 yards, and so on. When you know the distance to your target, and your load’s trajectory, determining elevation holdover requires only a simple calculation, which can be applied with the reticle itself or by dialing in elevation with the elevation adjustment. Windage compensation also becomes a major concern at long distances, something few hunters study extensively.

The specifications to the right are measured data for Thorlabs' absorptive neutral density filters. Damage threshold specifications are constant for a given optical density, regardless of the size of the filter.

The energy density of your beam should be calculated in terms of J/cm2. The graph to the right shows why expressing the LIDT as an energy density provides the best metric for short pulse sources. In this regime, the LIDT given as an energy density can be applied to any beam diameter; one does not need to compute an adjusted LIDT to adjust for changes in spot size. This calculation assumes a uniform beam intensity profile. You must now adjust this energy density to account for hotspots or other nonuniform intensity profiles and roughly calculate a maximum energy density. For reference a Gaussian beam typically has a maximum energy density that is twice that of the 1/e2 beam.

Please note that we have a buffer built in between the specified damage thresholds online and the tests which we have done, which accommodates variation between batches. Upon request, we can provide individual test information and a testing certificate. The damage analysis will be carried out on a similar optic (customer's optic will not be damaged). Testing may result in additional costs or lead times. Contact Tech Support for more information.

In part two of our series, we took a detailed look at the characteristics that make some modern riflescopes capable of extreme precision at distances well beyond 1000 yards. These characteristics don’t come cheaply, and is the reason why the best riflescopes carry price tags reaching $2000, $3000, even $4000 or more.

Thorlabs' Reflective and Absorptive Neutral Density (ND) Filter Kits offer our most popular filters prepackaged in convenient metal storage boxes. Refer to the Specs (Reflective) and Specs (Absorptive) tabs above for detailed information about the filters included with each kit.

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Pulses shorter than 10-9 s cannot be compared to our specified LIDT values with much reliability. In this ultra-short-pulse regime various mechanics, such as multiphoton-avalanche ionization, take over as the predominate damage mechanism [2]. In contrast, pulses between 10-7 s and 10-4 s may cause damage to an optic either because of dielectric breakdown or thermal effects. This means that both CW and pulsed damage thresholds must be compared to the laser beam to determine whether the optic is suitable for your application.

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Pulsed Microsecond Laser ExampleConsider a laser system that produces 1 µs pulses, each containing 150 µJ of energy at a repetition rate of 50 kHz, resulting in a relatively high duty cycle of 5%. This system falls somewhere between the regimes of CW and pulsed laser induced damage, and could potentially damage an optic by mechanisms associated with either regime. As a result, both CW and pulsed LIDT values must be compared to the properties of the laser system to ensure safe operation.

Use this formula to calculate the Adjusted LIDT for an optic based on your pulse length. If your maximum energy density is less than this adjusted LIDT maximum energy density, then the optic should be suitable for your application. Keep in mind that this calculation is only used for pulses between 10-9 s and 10-7 s. For pulses between 10-7 s and 10-4 s, the CW LIDT must also be checked before deeming the optic appropriate for your application.

This adjustment factor results in LIDT values of 0.45 J/cm2 for the BB1-E01 broadband mirror and 1.6 J/cm2 for the Nd:YAG laser line mirror, which are to be compared with the 0.7 J/cm2 maximum energy density of the beam. While the broadband mirror would likely be damaged by the laser, the more specialized laser line mirror is appropriate for use with this system.

Neutral densityfilter thorlabs

When pulse lengths are between 1 ns and 1 µs, laser-induced damage can occur either because of absorption or a dielectric breakdown (therefore, a user must check both CW and pulsed LIDT). Absorption is either due to an intrinsic property of the optic or due to surface irregularities; thus LIDT values are only valid for optics meeting or exceeding the surface quality specifications given by a manufacturer. While many optics can handle high power CW lasers, cemented (e.g., achromatic doublets) or highly absorptive (e.g., ND filters) optics tend to have lower CW damage thresholds. These lower thresholds are due to absorption or scattering in the cement or metal coating.

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As previously stated, pulsed lasers typically induce a different type of damage to the optic than CW lasers. Pulsed lasers often do not heat the optic enough to damage it; instead, pulsed lasers produce strong electric fields capable of inducing dielectric breakdown in the material. Unfortunately, it can be very difficult to compare the LIDT specification of an optic to your laser. There are multiple regimes in which a pulsed laser can damage an optic and this is based on the laser's pulse length. The highlighted columns in the table below outline the relevant pulse lengths for our specified LIDT values.

However, the maximum power density of a Gaussian beam is about twice the maximum power density of a uniform beam, as shown in the graph to the right. Therefore, a more accurate determination of the maximum linear power density of the system is 1 W/cm.

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Each set of filters is housed in a metal box for convenient storage and transportation. Additional storage boxes designed to house mounted Ø25 mm filters (KT01), mounted Ø2" filters (KT06), or unmounted 2" square filters (KT03) can be purchased separately.

The Ø1/2" Absorptive ND Filters are mounted in SM05 series lens tubes, the Ø25 mm Metallic and Absorptive ND Filters are mounted in SM1 series lens tubes, and the Ø2" absorptive ND filters are mounted in SM2 series lens tubes. In all cases the housing is engraved with the optical density. Same-size lens tubes are stackable, making it possible to create an additive optical density effect. The Absorptive 2" Square Filters can be mounted in our stackable filter holders, also making it possible to create an additive optical density effect.

The bottom line is that a shooter/hunter who invests the money into the best possible equipment, and most importantly, then invests the time and effort into constant practice and refinement of his techniques, is infinitely more ethical in his approach to hunting than the guy who shoots four or five rounds before hunting season and pronounces himself competent to take an animal’s life.

My forays into long-range shooting have not been without major benefits, though. I know that I have the optics, rifles and loads that are capable of more precision than I am. Having confidence in your equipment, knowing that it will not let you down in difficult circumstances, is of supreme importance when you are about to squeeze the trigger on a trophy animal.

The following is a general overview of how laser induced damage thresholds are measured and how the values may be utilized in determining the appropriateness of an optic for a given application. When choosing optics, it is important to understand the Laser Induced Damage Threshold (LIDT) of the optics being used. The LIDT for an optic greatly depends on the type of laser you are using. Continuous wave (CW) lasers typically cause damage from thermal effects (absorption either in the coating or in the substrate). Pulsed lasers, on the other hand, often strip electrons from the lattice structure of an optic before causing thermal damage. Note that the guideline presented here assumes room temperature operation and optics in new condition (i.e., within scratch-dig spec, surface free of contamination, etc.). Because dust or other particles on the surface of an optic can cause damage at lower thresholds, we recommend keeping surfaces clean and free of debris. For more information on cleaning optics, please see our Optics Cleaning tutorial.

CW Laser ExampleSuppose that a CW laser system at 1319 nm produces a 0.5 W Gaussian beam that has a 1/e2 diameter of 10 mm. A naive calculation of the average linear power density of this beam would yield a value of 0.5 W/cm, given by the total power divided by the beam diameter:

The calculation above assumes a uniform beam intensity profile. You must now consider hotspots in the beam or other non-uniform intensity profiles and roughly calculate a maximum power density. For reference, a Gaussian beam typically has a maximum power density that is twice that of the uniform beam (see lower right).

If this relatively long-pulse laser emits a Gaussian 12.7 mm diameter beam (1/e2) at 980 nm, then the resulting output has a linear power density of 5.9 W/cm and an energy density of 1.2 x 10-4 J/cm2 per pulse. This can be compared to the LIDT values for a WPQ10E-980 polymer zero-order quarter-wave plate, which are 5 W/cm for CW radiation at 810 nm and 5 J/cm2 for a 10 ns pulse at 810 nm. As before, the CW LIDT of the optic scales linearly with the laser wavelength, resulting in an adjusted CW value of 6 W/cm at 980 nm. On the other hand, the pulsed LIDT scales with the square root of the laser wavelength and the square root of the pulse duration, resulting in an adjusted value of 55 J/cm2 for a 1 µs pulse at 980 nm. The pulsed LIDT of the optic is significantly greater than the energy density of the laser pulse, so individual pulses will not damage the wave plate. However, the large average linear power density of the laser system may cause thermal damage to the optic, much like a high-power CW beam.

UV filter

When an optic is damaged by a continuous wave (CW) laser, it is usually due to the melting of the surface as a result of absorbing the laser's energy or damage to the optical coating (antireflection) [1]. Pulsed lasers with pulse lengths longer than 1 µs can be treated as CW lasers for LIDT discussions.

Thorlabs expresses LIDT for CW lasers as a linear power density measured in W/cm. In this regime, the LIDT given as a linear power density can be applied to any beam diameter; one does not need to compute an adjusted LIDT to adjust for changes in spot size, as demonstrated by the graph to the right. Average linear power density can be calculated using the equation below.

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According to the test, the damage threshold of the mirror was 2.00 J/cm2 (532 nm, 10 ns pulse, 10 Hz, Ø0.803 mm). Please keep in mind that these tests are performed on clean optics, as dirt and contamination can significantly lower the damage threshold of a component. While the test results are only representative of one coating run, Thorlabs specifies damage threshold values that account for coating variances.

Variable ND

I personally will never be an expert 1000-yard shooter. I simply don’t have the time or desire to make the commitment necessary to become proficient at such distances. In short, I’ve realized my limitations. Dirty Harry would be proud.

The sky was showing signs of light. It was opening morning, time to go. Jerry was still nervously waiting for an answer to his question, “how far is too far?” We had talked at length about ballistics, holdover, the effects of high altitude, his rifle and caliber, shooting techniques, all the things that sound great around a campfire but often serve only to confuse when the moment of truth arrives and you slide off the safety.

Now compare the maximum power density to that which is specified as the LIDT for the optic. If the optic was tested at a wavelength other than your operating wavelength, the damage threshold must be scaled appropriately. A good rule of thumb is that the damage threshold has a linear relationship with wavelength such that as you move to shorter wavelengths, the damage threshold decreases (i.e., a LIDT of 10 W/cm at 1310 nm scales to 5 W/cm at 655 nm):

Please note that these products are not designed for use as laser safety equipment. For lab safety, Thorlabs offers an extensive line of safety and blackout products, including beam blocks, that significantly reduce exposure to stray light.

I won’t embarrass myself by reporting how many rounds I shot that day. My groups were measured in feet. Even I could not shoot that badly. Or could I? I spoke with some friends at Nightforce, all experts in extended-range shooting, to help diagnose my problem. We quickly determined there were no problems with my scope or with my rifle.

Setting up on the bench, my first impression was just how incredibly far 1000 yards is. You don’t walk to your targets, you drive. As I prepared to shoot, I became aware of things that I had never noticed before. I could hear — and feel — my heart beating, each thump causing a movement of the reticle off the center circle of the target, a mere speck at that distance. Any excess tension in my hands or arms made steadying the crosshairs impossible. That slight breeze in my face — how would it affect the bullet over a half mile down range? Elevation was no problem — my reticle calculated holdover for me. But simply holding steady on the target was a monumental effort, both physically and mentally.

The adjusted LIDT value of 350 W/cm x (1319 nm / 1550 nm) = 298 W/cm is significantly higher than the calculated maximum linear power density of the laser system, so it would be safe to use this doublet lens for this application.

This scaling gives adjusted LIDT values of 0.08 J/cm2 for the reflective filter and 14 J/cm2 for the absorptive filter. In this case, the absorptive filter is the best choice in order to avoid optical damage.

As described above, the maximum energy density of a Gaussian beam is about twice the average energy density. So, the maximum energy density of this beam is ~0.7 J/cm2.

For many years I’ve worked with New England Custom Gun Service, a long-established supplier of fine long guns, hard-to-find components and sophisticated gunsmithing services. They have told me that 90% of the complaints they get from customers about accuracy can be traced directly to poor optics, cheap mounts, or improper scope mounting techniques. As you might imagine, a well-heeled shooter who just dropped 20 grand on a custom rifle is not pleased to find his new baby is spraying lead like a shotgun. NECG’s advice? Spend more on your optics than you do on your rifle. More so than in any other aspect of shooting, with riflescopes, you get what you pay for.

Accomplished competitive shooters recently broke the “three-inch barrier,” a goal that just a few years ago seemed impossible.  New world records of 10 shots in groups of less than three inches at 1000 yards are now being set, and broken, with regularity. It is a result of better rifles, better optics, improved bullets, and the application of technology that enables shooters to more accurately diagnose downrange conditions and analyze their own performance, much like a golfer might use video to identify and correct a hitch in his swing.

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“That might be your problem,” my mentor replied. “Most hunting bullets aren’t designed for extreme long-range shooting. They are built to dispatch a game animal humanely at reasonable distances. When you are sending projectiles to 1000 yards or more, you need to be using bullets designed specifically for stability and consistency over long distances. Very few ‘standard’ hunting bullets have those characteristics.”