This is my first time posting on this forum as I'm trying to gather all the information on this as I can. I'm a regular on ar15.com, but am looking for some class 3 experience/information. I'm gonna summarize this story, otherwise you can read it here My experience with Sabre Defence - AR15.COM Days prior to my form1 coming back approved, the LPK I had ordered for the designated lower came in. While installing it I determined the lower was out of spec. So now my form 1 is approved for an out of spec lower that was shipped back to the manufacturer. I was told by both the manufacturer an the ATF that they could not issue me the same serial on a new lower and that I was going to have to have my paperwork voided, refunded, and resubmitted. Now I'm not thrilled about waiting an additional 3-4 weeks to receive this new lower, waiting to get a refund, and then waiting for another approval. It has been mentioned by some that I can have the approved serial engraved on the new lower, and that this will suffice. I have been told by others that this is incorrect. I have yet to ask the ATF as I'm sure regardless, or with lack of knowledge they will tell me no. Anyone do this themselves, have people you know do this, or hear of this happening? Thanks.