Quote Originally Posted by dboyrollz76 View Post
I would say you need a stronger magnet. Yes to a point it’s non magnetic at first glance but I assure you that with a strong neodymium magnet you can pick any ferrous metal up. Not a little one, one of the 100-200 lbs force magnets wich you can only get from electromagnets or the large neodymium magnets, like we use in magnet fishing. If there is any iron in it, it sticks. How much is relevant to the quality of your stainless. The only thing it won’t pick up is nonferrous metals. A small neodymium magnet say out of hard drives. They are strong for their size but it’s not enough. The amount of carbon and magnesium in the alloy combinewith about 15% nickel 7% iron. Greater mass of non magnetic properties of the alloy make it seemingly impossible to stick to the metal. But if you increase the magnetic pull to over come the mass of the non steal properties. Undoubtedly it will stick. No questions asked. That’s one of the easiest ways to test the quality of the stainless. If a magnet that has 50lb strength sticks your stainless is junk. If it takes a 100lb strength your getting close to quality stainless. 200lb force is premium.
Unless you have spectrometer.

There are many alloys of stainless steel, with varying amounts of corrosion resistance. None of them are "junk". There are trade offs in anything. The additive in the alloy that makes SS corrosion resistant also disrupts the magnetic properties of the iron in the steel. So the more the steel responds to a magnet the less it will hold up against rusting. If you need your stuff to resist the highly corrosive environment of salt water, a magnet wont react to it. And yes, there is a point where you can effectively say it is no longer magnetic.

Very few of us are weathering our birds on a salt water beach - so swivels will last a long time even if they are made from a lower grade SS that responds well to a magnet.

Just using a magnet is not diagnostic of what the swivel is made of though. Brass is used in super cheap swivels that are prone to failures, and it is not magnetic either.