I took a client out to shoot his newer .380 Sig the other day. His Federal HS ammo worked fine....no issues. We only had 12 of those and switched to a new box of Hornady Critical Defense. These rounds would not fully fit into the barrel....even when done one at a time manually, with a locked back slide. Ergo, the slide would not close with a round in the tube. Tried pushing the slide closed with both thumbs to no avail. The rounds appear to not be seating into the barrel, when done manually. Any ideas would be appreciated.