Just measured, 20" barrel. So it looks like I'm good.
I'm a bit interested in changing the forend and stock to something different. I like the idea of wood. I also think it would better balance the long barrel. I was also interested in stripping the camo off (it appears factory), unless this is way too much work.
I did a little checking and my 500 doesnt seem to have the retaining nut at the front of the forend. Does anyone know what might be the case here?