Thanks for everyone's comments. Here is something I just came across on the Ruger website. It appears that Ruger kept the 330 prefix at least thru the beginning of 2009. There is no mention of what the prefix is for the beginning of 2010. I found this info under the customer service tab and...
Has anyone noticed that some of the new serial numbers for the SR9 have a prefix of 331 as opposed to the normal 330 prefix? Is there any significance to this new prefix?