BO, catalogue, default 50 items per page, I want 300. How do I change it?

[bargain-box]

When in back office in Catagories, I have a farming manuals section and right now there are around 130 manuals listed. Problem is, The default view is for 50 items and when I click to go to page 2 or page 3, I get a "INTERNAL SERVER ERROR" and have to go back. I tried setting my view to 300 items but when I come out of the page I see it reverts back to 50 items per page. How do I get it to show 300 items per page please?

Brian