If you would post the serial numbers of your Parkers we may be of some help. It is generally accepted that Parker Bros. made the chambers of a great many of their guns with chamber depths of 1/8" shorter than the length of the intended shell to be used. That said, I have two 12 ga. Parkers with 2 1/2" and 2 9/16" chambers that I regularly shoot 2 3/4" low pressure shells in. I believe the only thing that could happen from shooting standard 2 3/4" loads in these guns is increased felt recoil, presuming of course, that your barrels and chambers are in good shootable condition. Anyone with differing opinions will certainly chime in here.
