Recently I acquired a Mossberg 930 JM Pro shotgun and I miss the days of running an enhanced high visibility follower down the tube such as the ones that I would use when I had Mossberg 500's like this which are cheap and effective ($5): meanwhile the ones that are sold for the 930's run 3-4x the price of the simple polymer 500 versions. I've also noticed that most websites list the 590's in the same class as the 500's but sometimes the same as the 930 when it comes to followers. Items such as Or3Gun makes the follower like this: Which rides on the outside of the spring and runs you around $20. Why can you not use a 500 series follower on a 930/935 but you can use it on a 590? Lets look at the spring. The 930/935's use a spring that is the same inside and outside diameter from start to finish. The 500 and 590 series uses a spring that while the exterior is the same as the 930's there are a couple of coils at each end that are tighter wound and the interior diameter is decreased. Let's call this a tapered spring. This is why the 590/500 can use the same follower. This also explains why the 590 will share the follower with the 930/935. The 590 has the same external diameter and is tapered. I could have taken photos when I had the 590, 500 and 930 and given photo examples but maybe that will happen at a later date. In conclusion: a magazine follower designed for a 930 will work on a 500, 590, 935. a follower designed to work on a 500 will work on a 590 a follower designed to work on a 500 will not operate on a 930/935 a 590 will accept a follower from a 930 and a 500 (assuming it's using the tapered spring) Content creation.