Chad Nedzlek |
Being a unique magic item, the caster level, DC's, and price are set by the creator to whatever feels right. They probably went along the lines of "I feel like level 5 is a good level for a character to stumble across this cool little item, but making the DC 11 would mean no one ever failed, let's bump it up a bit to something a bit more reasonable for level 5, DC 14 seems fine, and let's give it a little +2 boost too, since it's a one use magic item, and it would be sad to miss".
Dave Justus |
That is the caster level OF the item, not the caster level requirement to create it (you are correct that +2 requires a CL of 6, but the item can still be made with a lower caster level.) Usually the caster level of the item only matters in regards to things like dispel magic.
Although the Screaming Bolt is based on the Level 1 Doom spell, it has a somewhat different effect, being an area, not a single target. The writer apparently (and I think justifiably) decided this was a 3rd level spell effect and that is what set the caster level and the DC to 14 (just like a 3rd level wand.)