Homebrew Magic Itens - Spells

When creating a homebrew magic item you can add a spell to it and set a specific save dc for that spell, but if it's a spell that requires an attack roll? Can't you set a specific attack bonus for the spell?

Quote from spamandtuna >>

I don't think that's currently possible, no. If you happen to find an official item that works like that, though, you could make a homebrew copy of it to see how it was set up.

The Circlet of Blasting is supposed to work like this, but it doesn't actually work correctly. When added to the character sheet it uses the character's spell attack modifier instead of the specified +5, and creating a homebrew copy just puts the phrase "Spell attack bonus +5" in the Details field.