Silva Expedition 4

One of Silva of Sweden's best all-around field compasses, the Silva 4 Expedition is the company's full-sized baseplate compass that has been in production for years.

In service with several military forces for a couple of decades now, the Silva 4 in civilian form is a rugged orienteering or protractor-style compass designed for wilderness navigation in conjunction with a topographic map. The Silva 4 Expedition has 1:25k, 1:50k, and 1:63.36k map romer scales, as well as inch and millimeter map measuring scales. It has a stable needle, easy-to-read two-degree markings, and luminous points for navigation in the dark.

Unfortunately, the Silva 4 isn't available in North America, apparently because of a trademark dispute with Johnson Outdoors (JO), who owns the Silva brand name there. JO doesn't offer a fullsize baseplate compass of this type. While Silva of Sweden owns Brunton and has released other Silva of Sweden compasses under the Brunton and Nexus brand names in North America, for some reason it has not chosen to import the Silva 4. So if you want one, you'll have to order from a dealer outside North America.

I have used the Silva 4 for years and can highly recommend this model. I've found its long baseplate makes accurate sighting to nearby landmarks easier than compasses with a shorter base, while allowing easy plotting of bearing legs on a map. Even with its long baseplate, it's still less bulky and more versatile than the various Brunton Eclipse models.

While it has no sighting mechanism, it doesn't really need one, as the Silva 4 has never prevented me from getting accurate bearings for real-life wilderness navigation (nor might I add, has it been a problem for the British Army and other military users!) Its long, clear baseplate doesn't obscure map details when deployed. I think the Silva 4's compass dial or bezel is one of the best for visibility and easy of use, and it has reasonably bright luminous markings for use in low light or darkness. It comes with a rather short lanyard that I always replace with a longer version, but that's a personal choice.

North American users, especially those also carrying GPS receivers, should be aware that the Silva 4, as a non-USA model, does not have a 1:24k romer scale printed on its baseplate, though its 1:25k romer scale is close enough to the 1:24 scale of U.S. topos to permit accurate GPS plots (within a few feet). Of course, the 1:50K romer is ideal for Canadian topo map users.

While there is no adjustable declination mechanism, the Silva 4 does have a printed declination adjustment scale for those that can add and subtract (or just carry a reminder card in your compass pocket).

I have owned four or five of these over the last 25 years and they have served me well in the Scottish mountains in winter, Norway, Switzerland, Italy, France (4000 metre peaks etc, North America, New Zealand, India etc. Absolutely foolproof once you have learnt to use them PROPERLY.

I have navigated in every weather condition imaginable and it has been a life saver in white out and blizzard conditions. The compass is tough and durable and much more accurate than one would imagine. Just make sure you know how to account for magnetic variations etc and how to compensate for this.

One thing I can't understand is why the US doesn't join the 21st century and go metric. It works on base 10 only, using universal integrated calibration across, distance, volume, pressure, etc. It is based on scientific fractions of the Earth and its properties: not the length of some blokes foot or thumb etc.

I was taught in the old imperial system, but have used metric measurement most of my life, and boy does it make life easier, and MISTAKES so much less likely. Maps here in the UK and the rest of Europe are 1:25,000 and 1:50,000 scale mostly, with each grid square representing 1km and contours at 10m intervals. I felt like I was going back to the dark ages when I used American maps in the mountains of Colarado and Washington state.

My Thommen altimeter is calibrated in metres as were ALL my Silva compasses. Come on America, you might still be the main Honcho as they say, but Europe has got it right with the metric system!