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User Guide for Mil-Dot Equipped Optics By: Michael Haugen Division Article 2005.12MH

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User Guide for Mil-Dot Equipped Optics By: Michael Haugen Division Article 2005.12MH Division Article 2005.12MH User Guide For Mil-Dot Equipped Optics By: Michael Haugen Division Article 2005.12MH This guide is intended to provide the user of a Mil-Dot equipped optic with information on what the reticle is used for, the basics of its use and how to train your- self to better employ and realize the full potential of this reticle. DISCLAIMER THE INTENT OF THIS DOCUMENT IS TO PROVIDE SOME INFORMATION TO ENABLE USERS OF MIL DOT EQUIPPED OPTICS TO DEVELOP SKILL IN THEIR EMPLOYMENT. THE ACTUAL USE OF THIS INFORMATION IS THE RESPONSIBILITY OF THE USER. MISUSE OF THIS INFORMATION COULD RESULT IN LEGAL RAMIFICATIONS. TREAT ALL WEAPONS AS IF THEY ARE LOADED, NEVER ASSUME THIS AND BE DEADLY SERIOUS ABOUT IT. NEVER USE UNSUSPECTING OR UNAWARE INDIVIDUALS AS MIL PRACTICE OBJECTS. THIS DOCUMENT IS NOT ALL INCLUSIVE; IT TAKES PATIENCE AND PRACTICE TO BECOME SKILLED AT ALL SHOOTING ASPECTS. NO AMOUNT OF MONEY OR DEVICE IS FOOL PROOF MEANING THAT YOU CANNOT ìBUY SKILLî. USERS SHOULD PRACTICE ANY AND ALL TECHNIQUES POSSIBLE TO DEVELOP APPLICABLE METHODS. GENERAL INFORMATION Congratulations on your recent purchase or interest in the use of an optical product that features the mil-dot reticle. Lets begin by issuing a disclaimer; some of you out there may find some controversial information contained in this manual, however this information has been verified and tested by a variety of professional sources. Whether you are a beginner or a seasoned user of mil-dot equipped optics, you will find something useful contained in this document. There are three basic reasons that people purchase optics with this reticle; to estimate range, lead moving targets and/or to hold off for winds. The problem with this reticle is that it requires a little training and some practice. Having said this however, this reticle is extremely versatile and useful and when properly used will allow the shooter to accurately engage and hit targets at ranges previously thought impossible. In the beginning, new shooters will doubt the accuracy of this system because ranges they previously thought were quite distant equate through the math to be significantly closer than expected. This is very typical because most shooters vast- ly over estimate range. As time goes on with more practice you will notice that your ability to estimate range by eye will dramatically increase which in turn will serve as a “check” against your “miling” allowing to quickly estimate the range and engage the target. WHY USE MIL DOTS This is probably the most asked question in reference to reticle patterns. The short answer is that the mil dot reticle once learned is not only a simple but extremely versatile tool. There are any number of “range finding” reticles on the market that promise any number of things, however they all are attempting to do the same thing but with less effort on the oper- ators part. The largest difference between most of the “other” reticles and mil dots are in many cases the other reticles are built around a specific caliber and load; dramatically decreasing shooter versatility. Other reticles require the use of every- thing from “cheat sheets” to palm top computers in order to be functional. While there is nothing “technically” wrong with a cheat sheet or a palm top, it definitely makes for an interesting shooting experience when the cheat sheet gets lost and the batteries die in the computer. Point here is that mils dots are the standard by which everything else is measured, they are as ingenuous as they are simple and as I have said elsewhere in this document; once learned they will provide the tac- tical shooter and hunter with a tool that will allow him to do things he could not before. Most people who do not like them or badmouth them do not know how to correctly use them. Lastly, if you personally do not like mil dots do not use them. Use what makes you feel comfortable and assists you in hitting the target, but I challenge each and everyone who reads this to give them a chance; try to learn them and practice with them before you cast them out. WHERE DID MIL DOTS COME FROM AND WHY ARE THEY USED? The milliradian is an engineering term for a unit of trigonometric measurement; specifically a milliradian is used in the engi- neering community to measure angles as derived from a circle (verses right angles). The engineering community uses 6283 milliradians to a circle. Earlier in the 20th century, the U.S. Infantry used “Mils” (see specifications for definition and value) to correct the trajec- tory for indirect fire and crew served weapons. This was done mainly because Mils are a finer measurement than degrees and enabled them to be more accurate. The Infantry divided a circle into 6280 parts or 1/6280th = 1 mil. This was a slight deviation from the truth but it was easier for them to compute, work with and provided even number results. The Artillery Division Article 2005.12MH also decided to use this system, but concluded that 6280 was not fine enough for accurate precision fire. They rounded the number to 6400, which equates to 1 mil or 17.8 mils = 1 degree. This system became institutionalized and remains widely used in all services today. It should be noted that the term “mils” relates to the military variation whereas “milliradians” remains an engineer- ing term. The USMC was the first U.S. military service to in corporate a mil dot reticle in sniper optics by having it installed by J. Unertl for use on the M40 sniper weapons system. When the Army decided to incorporate a range estimation tool into it sniper optics it chose this system and had Leupold make the reticle accordingly. I should clarify this point for those out there not familiar with the Leupold M3A Ultra currently used by the US Army. Many people believe that the Mark IV M3 that they see advertised by various retailers is the same as the optics on the Army M24. Although they are identical in appear- ance, they are not the same. Specifically the reticles are different; the M3 Ultra uses an etched glass reticle with round or Army mil-dots, whereas the available Mark IV M3s sport a wire reticle with the USMC oblong dots. Since the U.S. military adopted mil dots for use by its snipers, this reticle pattern has become a favorite of law enforcement, varmint shooters and hunters. Recently there has been a lot of discussion (read argument) around whether or not the Army and the USMC use differ- ent moa values on their reticles. A call to the Leupold engineers will result in their stating that all Leupold reticles (military or commercial) use 3.438 (same as the USMC), however every Army manual or reference states that 3.375 is the correct number. So what is the correct number? Research into the original Army requirements documents shows only the physical distance between dots and that it equate to 1 mil, however further discussions with the engineer reveal two things; a mil is a military term and that the Army only recognizes 6400 mils to a circle which in turn equates to 3.375moa to a mil. Why then did the USMC go with 6283 or 3.438. The answer probably lies in the fact that an engi- neer more than likely developed the reticle using the dots and because it was an engineering term stuck with the 6283 being unaware of the 6400 number. While all of this makes for a great argument, the last interesting part of the research revealed that the error acceptance on the Army reticle exceed the difference between the two (Army and USMC). Therefore the actual value could and probably is somewhere in between. The shooter using either reticle will never realize the difference in mil value (NOT dot size or measurement methods). The end result; use 3.5 moa to a mil and practice. It should also be noted that MG (ret) Julian Hatcher states in his book “Hatchers Notebook” first printing August 1947 on page 403 “one mil = 3.375 moa”. If you are a purest, use 3.375 for an Army type reticle and 3.438 for a USMC type reticle, otherwise use 3.5 for either. The popularity of the mil dots has resulted in them being offered by virtually every optic manufacturer today. This interest has also resulted in numerous variations being developed by several companies at the request of users. Most of these vari- ations come in the form of dot spacing and number of dots presented. The most exciting news in the mil dot reticle world is the recent development of the GEN II Mil Dot reticle offered by Premier Reticle, which dramatically increases the versa- tility of the reticle. Regardless of which version of reticle you have purchased, I HIGHLY encourage you to read this manual and PRACTICE, PRACTICE and PRACTICE and you will have a system that is time and combat proven to deliver reliable and consistent hits to maximum effective range of the weapon it is used on. MIL-DOT SPECIFICATIONS The term or measurement of Mils used to configure and use the Mil-dot [equipped optic] in estimating range. Here are the engineering (or true) specifications. 1 Milliradian = 1/1000th of a radian, 1 radian = 2 PI (6.283185306) 1 Milliradian = .0573 degrees or 6283 parts of a circle As I mentioned in the previous section, the military changed the engineering measurement to suit their needs.
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