Spoke Length Question
 

Hello, I'm rebuilding my Campagnolo Record large flange hubs and Weinmann 27" rims. I'm wondering if I can use 12" (305 mm) spokes instead of the 307 mm spokes it came with. Thank you in advance.

The answer is in your hands (or will be when you pick up your wheel).

It's important that spokes reach fully up into the heads of the nipples, ending somewhere (ideally) between the bottom of the screw slot and the top of the nipple as shown below.
http://bikeforums.net/attachment.php...hmentid=448018

If the 307's are near the long end of the range, then losing 2mm is OK. But if the 307s are barely reaching the screw slot or shorter than that, then you really don't have another 2mm to give up.