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There are three outstanding map protractors to consider for your land navigation needs. Land navigation is an essential part of both emergency survival and enjoying the outdoors. Many people prefer to use GPS devices such as those from Garmin®. Other people prefer to use some kind of GPS and Map application on their smartphone or tablet. However, land navigation with a paper topographic map can be cumbersome without the aid of a map protractor and a compass. Therefore, it is good to know the two basic kinds of map protractors.

Map protractors have some essential functions regardless of their calibrated scale. The three primary functions of protractors for map reading are plotting points on a map, measuring distances and determining azimuths (angles). They are helpful tools for navigating on air, land, or sea. There are different types of protractors for each of these applications. This article will focus on those protractors used with land navigation and topographic maps.

1. Military Map Protractor

 

Description

The most recognizable map protractor is the one that is in use with the U.S. military. They are scaled to the Military Grid Reference System (MGRS). They use the metric system for measuring distance and feature both compass degrees and mils around the edges. These protractors are for use with the military topographic maps. This style of the protractor is available on the civilian market. However, some are scaled for commercial maps, like a UTM map, rather than military maps. Also, you can find military protractors sometimes being sold in military surplus stores.

The significant difference between the genuine military protractors and the civilian copies is labeling. There is a label on the military-issued ones that reads something like this:

GTA 05-02-012, June 2008
DEPARTMENT of the ARMY
GRAPHIC TRAINING AID
Title: COORDINATE SCALE
AND PROTRACTOR

There are military style map protractors available by civilian vendors online. However, they are prohibited by law from putting the above label on them. Why? Because once a company does that, the product becomes the property of the U. S. government. Since they may not be under contract with the Department of the Army to supply these products, they would be in violation of the law if they put the U. S. Army label on them.

Primary Use

Moreover, military protractors and maps are for use in training and operations. Thus, genuine military protractors and military topographic maps have to be updated often. The purpose of these updates is to account for the changes in the magnetic declination of the earth. For example, if you have a genuine military protractor with a date from the 1990s, it may not be as accurate as one with a more current date. For civilian use, this factor is not as critical to land navigation.

2. UTM Map Protractor

 

Description

A commercial version of the military map protractor is the UTM map protractor. UTM stands for Universal Transverse Mercator. UTM is based on the metric grid square system of measuring distance. It has similarities with the MGRS system. These protractors have two basic styles: the military style and the nautical style. The maritime version of this protractor incorporates both topographic map scales and marine navigation tools. The sailing version looks complicated to read. However, it is not that much different than the military MGRS protractor.

Primary Uses

The UTM map protractor is most useful with civilian topographic maps, such as the ones that you can purchase from map stores. In some cases, the UTM protractor can be used with non-topographic maps. However, these protractors may not be compatible with your typical road atlas map book. So be careful about how you use one of these protractors on maps purchased at your local store.

UTM maps and protractors are mostly used for hiking and backpacking. A common way of reading UTM coordinates is “Northing and Easting.” UTM squares are further divided into kilometers similar to the MGRS system. UTM is similar but different from the MGRS system in the way that it is read and annotated on a map.

3. Corner Rulers

 

Description

The third kind of map protractor are the corner ruler protractors. These look similar to the UTM and MGRS military-style protractors. However, some of the features are different. Corner Ruler protractors do not have any compass degree markings around the edges. Next, the grid-square scale is upside down. They are designed to find a coordinate with a known grid quickly. They are not intended to find grid azimuth readings on a map and route plotting.

Primary Use

The Corner Ruler map protractor has a primary use in two applications: aerial photography and adventure racing. Their use for aerial photos is to quickly find a point on the photo within an identified grid square. Adventure racers operate on predetermined routes. Therefore, they do not need a tool that helps them traverse over open terrain by plotting a course. They just need a protractor to help find where they are on a known grid-square.

Some Final Thoughts

Map reading and land navigation are vital skills for those who love the outdoors. It is also an essential skill for emergency survival. I have found that some trail maps that are available at a trailhead or ranger station are little more than sketches. They are not to scale and are not very accurate. If this is your only map in your backpack and you get lost, a map like that might be your worst enemy.

It is vital to have an up-to-date and accurate topographic map of the area you are operating in. Along with that map, you should also have an excellent manual compass and map protractor. The MGRS and UTM protractors are the two most common kinds of protractors available. Some companies sell map protractors with both MGRS and UTM scales. Therefore, shop around and find the protractor that you are most comfortable. Then, use it regularly with your hard-copy topographic map.

The best compasses for your kit considerations are those of proven quality, durability, and accuracy. The compass that you choose to include in any level of survival or outdoor packing list is one of the essential items in your loadout. As well, there are strong feelings among many about what brand or type of compass is the best on the market. However, the best compass on the market is the one that you have used and are the most confident with when you are in the field. However, the best compasses for your kit are the following:

1. U. S. Army Lensatic Compass

The U. S. Army Lensatic Compass conforms to the military standards published in MIL-PRF-10436N. Also, the military lensatic compasses are made in the United States. The current manufacturer of this compass is the Cammenga Company in Dearborn, Michigan. Of note, the previous maker of these compasses is Stocker & Yale, Incorporated in Beverly, Massachusetts. For example, the two lensatic compasses that I own are from Stocker & Yale. Moreover, you can purchase one of these Cammenga military lensatic compasses at the Sigma 3 Survival Store.

Description:

A lensatic compass is a magnetic compass that uses a magnifying glass to read its scale or dial. The U. S. Army lensatic compass is an induction-damped, handheld, north-seeking instrument with an internal, self-exciting light source, in other words, it is self-illuminating (tritium or phosphorous). The baseplate construction is of high-grade aluminum with a powder coating. The needle moves within a non-liquid filled needle housing. Thus, the military lensatic compass is one of the best overall compasses on the market.

Features:

Cammenga makes this compass with two options: model 3H with a tritium luminous dial (NSN: 6605-01-196-6971) or model 27 with a phosphorous luminescent dial (NSN: 6605-01-571-6052). Interestingly, Cammenga produces these compasses in the following colors: Olive Drab, RealTree® Camo, Black, and Coyote Brown. The compasses have a free-floating needle instead of the needle floating in a liquid (water or oil). They are also waterproof and dustproof under most field conditions. They will function in temperatures between -50°F (-46°C) and 150°F (66°C). The compass is also shockproof is dropped from up to three feet (90 cm). Additionally, they also have two needle options: Northern Hemisphere and Southern Hemisphere.

Additional Comments:

Moreover, the lensatic compass is the standard compass in all my backpack load outs. I have other compasses, but my U. S. Army lensatic compass is the one that I keep coming back to when I need reliability, durability, and accuracy. Most of all, I do not have to wait for satellite synchronization or linkage with the lensatic compass. There are no extra batteries that need to be carried in a pack because it is an analog magnetic compass. In addition to these features, the military lensatic compass also fits comfortably into the LC-2 ALICE First Aid Pouch or the MOLLE Grenade Pouch.

Best Uses:

Advanced and Tactical Day and Night land navigation
Orienteering
Hiking & Backpacking
Game Hunting

2. K&R Alpin Sighting Compass

The next type of compass that can be part of your loadout is the mirrored sighting compass. One of the best on the market is the K&R Alpin Sighting Compass. The compass is a product based on input from the German Mountain Rescue Service. These compasses are made in Germany.

Overview:

A mirrored sighting compass is a compass in which the compass dial can be viewed using a mirror while simultaneously sighting an object through the sighing notch or slot on the compass lid. That is why these kinds of compasses are not in the category of being a lensatic compass. The sighting compass is sometimes called the hand compass, forester compass, or cruiser compass. They are one-hand use compasses. Their easy use quickly found them being a favorite of the geology, marine, and forestry professions.

Features:

The Alpin Sighting Compass has several convenient features. The sighting mirror is polished stainless steel. The baseplate, compass lid, and compass capsule are made of high-impact plastic. The result is a compass that is very durable and lightweight. The needle moves within a liquid filled needle housing. The bezel is self-luminating with two large sighting notches (12 and 6 o’clock positions) on the bezel for night navigation. It also has a clinometer to measure incline while traversing uneven or mountainous terrain. K&R has three measurement options for this compass: standard, metric, and mils.

Additional Observations:

This particular compass is an excellent alternative to the military lensatic compass. The large glowing bezel makes it user-friendly for trekking at night. It is easy to use and probably a better option for those unfamiliar with using the military lensatic compass. A rival to the Alpin is the Suunto MC-2 Sighting Compass. Both of these compasses fit comfortably into the MOLLE Gen II Flashbang Grenade Pouch. The K&R Alpin and the Suunto MC-2 compasses represent the best of the mirrored sighting compasses on the market.

Best Uses:

Advanced Land Navigation
Orienteering
Hiking and Backpacking
Game Hunting
Emergency Preparedness

3. Suunto M-3 G Compass

Finally, a third type of compass option for your outdoor activity concerns is the simple baseplate compass. The baseplate compass is the most common type on the market. One can purchase these kinds of compasses with various levels of quality and in various price ranges. The primary use for the baseplate compass is in conjunction with a map.

Description:

Baseplate compasses have a clear plastic base upon which the compass mechanism sits. The sides of the baseplate usually are marked in standard increments. These markings allow the baseplate to function as a ruler for measuring distances on the map. The baseplate also has a magnifying glass embedded for observing small map details. The needle mechanism usually is liquid filled and jewel bearing.

Features:

The Suunto M-3 G Compass has several useful characteristics. The bezel is luminescent. The G model has a globally aligned needle so it can be used anywhere on the earth in both hemispheres. This model also comes in just a northern hemisphere (NH) needle orientation and a southern hemisphere (SH) needle orientation. It is incrementally marked in metric and imperial UTM scales. The compass also has a clinometer for determining the slope of an incline. This compass originates in Finland

Additional Observations:

The baseplate compass is one of the most versatile compasses that one can own. The Suunto M-3 compasses offer the basic navigational needs for most scenarios and applications. They are small enough to fit easily into a MOLLE Flashbang Grenade Pouch. They come with a lanyard which allows attachment to the shoulder strap of most backpacks. These compasses are easy to use and are an excellent option for the occasional outdoorsman or weekend hiker or backpacker.

Best Uses:

General Land Navigation
Hiking and Backpacking
Game Hunting
Emergency Preparations

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