Sight and barrel question

[hokusai]

I changed the front sight on the barrel of my mossberg 500a. I purchased the sight directly from Mossberg's site. This new sight screwed in fine but the threading does not sit flush within the inner barrel. Do I need to file it down?

[JJ1911]

I had a similar issue installing a new sight for my 590. I was told to put the new sight in, see how much it sticks out, remove the sight, file it down, then reinstall. Do NOT under any circumstance try and file the sight while it is installed, you don't want to start filing part of the barrel. Hope this helps.

[hokusai]

Thanka JJ. You definitely helped.