Home Forums Hunting & Shooting Backpack Hunting Declination for Dummies???

Does a book exist? The more I read about it the more I confuse myself. I am trying to learn all I can about using a compass. I know the question I want to ask, but is difficult to ask without pics and face-to-face conversation.

Let's say I am hiking in western CO, and have drawn a line on my map connecting point A to point B. Now I want to figure the bearing from A to B. I have oriented my map with compass and am dealing with declination of 10 degrees E. Let's say I will be heading in a NW direction to get to point B. So I line my compass up with the line and do my thing, and determine my bearing to be 340 degrees. Is my actual bearing accurate at 340 degrees if the map is oriented? Or do I need to subtract or add 10 degrees? Is declination canceled out if the map is oriented? Or is declination always in effect, whether oriented or not.

I can understand when I orient my map that M-north is east of T-north, but I tie myself in a knot trying to decide if I then add or subtract the declination.....I know that it is simple, but I am not getting it just yet.

Thanks,
Brent

If you orient your map to true north (not magnetic) then declination has already been accounted for. Set your compass for your bearing and you are good to go.

there actually is a pretty decent book out there - I bought it years ago when I was teaching my sisters navigation.

I'll try to look up the title tonight.

I also have a word doc and a word doc = quick ref cards for lamination I made for them (if you're interested).

I could e-mail them to you - this won't let you attach word docs here.

Good question, especially for those of us who don't use a compass daily, and maybe only a few times a year for such work.

The truly knowledgeable are aghast but when I need a compass bearing and haven't done it for awhile, I re-learn or think it through each time. I orient my body to my best guess at facing the North Pole, think where magnetic north is (to my right at about a 23 degree angle in my area) and think my way through what that means in terms of adding or subtracting declination from where the compass actually is pointing, lifting a bearing off a map, transferring a visual bearing to a map, etc.

It may not work for anybody else but works for me. Slogans like east is least and west is best, etc. just confuse me.

If I am shooting a visual bearing, toward a distant peak or merely a tree on a ridge where a wounded animal went out of sight, I ignore declination and just follow the bearing the campass points.

The quick ref card Lefty mentions would be excellent for those of us who don't use a compass often enough to keep it fresh in mind.

I have trouble with that one too. Most times I know where I'm going (mostly ) and don't use a compass a lot.

Matt- would you email that to me too please?

I will Mike.

Matt, if you have time send one my way also. Thanks!!!--Allen--

Thank you sir.

need an e-mail addy!


welcome Mike!

I picked up a great book a few years ago called "Wilderness Navigator" by David Seidman. It was released by Ragged Mountain Press. It covers more than I'll ever need to know....so much that I no longer carry a gps.

Could you email one to me, too, please? Thanks in advance.

Well, here's the most important thing one needs to know about declination, or any form of land navigation for that matter...

Lewis and Clark were never lost... They just didn't know where the [bleep] they were

I'm cool e-mailing the files to those that ask - but you have to either pm me your email or have it in your profile. It' won't attach a .doc to a pm any better than to a public thread.

"The essential wilderness navigator" is in fact the book I was referring to, I do believe. I have an older paper copy.

It's available as a free Google book online here

my bad, I thought it showed on my profile.

melgtf14charter.net

should be there tx.

here is a fantastic instructional site...
geared for the mil-type lensatic compass, but has a huge amount of info.

http://landnavigation.org/default.aspx

this has long been considered a classic. I learned with it as a boy and still reference it.

http://www.amazon.com/Be-Expert-Map-Compass-Orienteering/dp/0020292651

my quick tip is this. draw declination lines on your paper map with a pencil. Line you compass up with them and go. You can draw the first one straight of the declination angle on the quad using a yardstick. draw the others parallel to that at your prefered interval. A fast and quick field method to align Magnetic North Compass to Map.

You beat me to it Mac, that's what I was gonna say, as far as drawing the declination lines on the map. To add a few more words of explanation, if your declination is 10 degrees east, draw a series of parallel lines on your map that are 10 degrees east of north. When you lay the compass on the map with the edge aligned from point "a" to point "b" rotate the round housing (without moving the compass on the map) so that the lines on the round housing parallel to the north arrow are parallel with the declination lines on the map, with the north arrow pointing to the top. Now you can read the bearing, corrected for declination.

To get to your destination, hold the compass in your hand and rotate your body so that the magnetic needle is centered in the north arrow, and you're pointed in the right direction.

Also, check out these guys, they have good on-line tutorials:

http://www.us.orienteering.org/Home.html

If that fails, books on aircraft navigation also go over declination. If you think you can get lost in the wilderness on the ground with the wrong declination, you should see what you can accomplish in the air at 100 knots.