Compass & Navigation

**GVC86** · 05-09-2013, 15:28

Hi guys,

Thought of putting this in the bush craft/survival section but the remembers that navigation is part of the level 3 test, thus the SaS guys should be able to help.

1. Which compass do you prefer?
I like the lensatic compass like the military uses (USA, don't know which our forces use) and need some instruction on use.

2. Also which brand?
I bought a lensatic compass that I thought was of great/good quality, just later to find out its a fake.

3. Where to purchase & price?

Thanks
George

Sent from my BlackBerry 9380 using Tapatalk

**krieger** · 05-09-2013, 22:53

Cammenga 3H tritium is what we use.

cammenga.com

Make sure you select the model for the southern latitudes.

**Dirk777** · 05-09-2013, 23:31

Use any compass with a sighting mechanism. Test it.... and it should be good to go.
I used an inexpensive one at the bush weekend, and the Delville Wood comp. It really helps to know the conversion from true to magnetic north. Fortunately I had JS4 and Camo 762 in my team.

**Dirk777** · 05-09-2013, 23:46

Variation is West in SA. Add to True for magnetic.

JS 4 will you add please

**krieger** · 05-09-2013, 23:54

Magnetic declination calculator here

http://magnetic-declination.com/

Search for Marine Corp land navigation pdf
It is a complete compass land nav course.

**ikor** · 06-09-2013, 00:47

Originally Posted by krieger

Magnetic declination calculator here

http://magnetic-declination.com/

Search for Marine Corp land navigation pdf
It is a complete compass land nav course.

IIRC this is it...

http://www.enlisted.info/field-manua...vigation.shtml

**krieger** · 06-09-2013, 02:57

Thats it Ikor. I couldn't remember the site.

Learn your map and compass because if the shooting starts in the Med civilian GPS will be turned off.

**JS4** · 06-09-2013, 04:04

Originally Posted by Dirk777

Variation is West in SA. Add to True for magnetic.

JS 4 will you add please

Correct.

Variation (or declination - same thing different term) is the difference between the True and Magnetic North poles as measured in degrees from the True North.

It will differ from place to place depending on where you are and is normally indicated by a diagram on the map border, isogonals (lines joining places of equal variation on a map - in the same way that isobars join places of equal atmospheric pressure) or both.

Variation is termed Westerly if the magnetic North pole lies to the West of the True North pole, and vice versa. In order to convert a True bearing (as measured on a map) to a Magnetic bearing (as you would read from your compass) Variation needs to be applied.

With a True bearing being measured in degrees from True North and a Magnetic bearing being measured from Magnetic North, it follows that Magnetic bearing = True bearing plus Westerly OR less Easterly Variation.

In order to obtain Compass bearing one actually needs to apply Deviation too but that only applies to compasses fixed in pieces of metal such as vehicles and aircraft.

As Dirk said, any compass with a sighting mechanism will work.

**GVC86** · 06-09-2013, 07:05

Thanks guys,

Ikor & krieger,
I saw those on the net very nice,just hope I can find a local dealer in south africa. Thanks for the link will download and study.

JS4 & Dirk777,
Thanks but I think I'll need some tutoring on the subject, will study those docs ikor and krieger supplied the link for.
What brands do you use and where to buy? Struggling to find decent equipment in my small town.

Thanks
George

Sent from my BlackBerry 9380 using Tapatalk

**Bushboy** · 06-09-2013, 07:40

A good brand is Silva, but expect to pay. They dont show direction any more effectively than say an el'cheapo compass, but they are generally better built, have nice user friendly functionality and the numbers dont wear out in a week. The ones you get from Army surplus are not bad at all. Just make sure the one you get is not damaged and it will serve you very well.