Home Forums Hunting & Shooting Hunter's Campfire Magnetic Declination

Easy to mess up on a land nav course, especially under duress! That's why we train, and I have seen the best of the lot miss a point and have to backtrack and refigure, including me! I messed up at Camp Darby once!

Bob, I never shot Polaris while working, but we had a crew that did. I did do a lot of sun shots, using an HP calculator to compute the results, but we never compared the results to magnetic North. Later it was all done with GPS. When I first started to work back in the 1960's, out transits had an offset, set in the instrument, but it turns out that they were all over the place with different crews, so we set all of them back to zero, and the correction was applied in the office. It has always been a confusing thing to most people. Kinda like ground and grid coordinates. miles

Back before GPS it was 9 degrees East here, now I see it’s it’s 3.86 which we woulda called 4.

Back in the day I used to have to find pieces of old rebar on Camp Bullis, hammered into the ground to mark bird sampling points, laid out in a line, random start and direction, each point 200m apart on the map (actual walking distance varied with terrain.

Tough to find a rusty piece of rebar a foot tall back in the woods, but made much easier by contour lines in that hill country setting. Still, it was lots of practice with pacing and heading.

I found all kinds of stuff dropped or forgotten in training areas, one time a compass, looked to be military issue. I was disappointed to find it had no provision for setting declination.

So I dunno if they were supposed to do the math every time they took a bearing, or else they just gave them headings to use without them having to worry about declination.

Our shot was not 7 degrees north as I stated. It was like 7 degrees east. I don’t know how close it was to actual. This was done at night with a rod and lantern after a bottle or two of Bordeaux.

Every military compass I've used had a way to set declination. There are a lot of cheap military knockoffs on the market for as little as $10. You wouldn't want to bet your life on one.

Are you lost, again?

well I guess the poles flip from time to time...
why should anything stay the same on a living planet??

I know that I can set the declination on the electronic compass in my car and most silva type compasses have a means of setting declination...(though I seem to recall that it is not intuitive...

next thing you know we will be hearing about the magnetic shifting crisis on the news..

it certainly allows NOAA to sell more chats...(another source for declination is navigational charts (air or sea and probably topo maps too)

From time to time is a long time. The last flip was estimated to have been over 700,000 years ago, a bit before the compass was invented. Everything that they say will happen when it flips is largely speculation as nobody really knows.

that long ago? I remember seeing a chart of flips I think it was tied to oil exploration and dating the rocks that they are drilling....or maybe it was in ice cores in a book about a buried alien space ship...
thanks for adusting my frame of reference...

Here's a diagram of how the north magnetic pole has been moving.
I haven't figured this out yet. Here in Idaho, MN is east of TN. Yet, according to this map, it's west of it. Maybe it looks different on a round globe.

Then there's the geomagnetic north. I have yet to find a description of what it is written in layman's language. It's not the same as magnetic north and a compass points to MN. However, many of the maps I've seen show GMN for a compass bearing, not MN. I'm lost on this one.

Never been lost. 😉

Well then, you're not trying hard enough.

There was this one time I briefly did not recognize my surroundings.