BeemanR7...you beat me to it. The barrel IS fully seated in the breach block....but it is not protruding far enough to catch the cut out in the Side-Shot magazine. The grub screw has made only one witness mark on the barrel in one spot and the barrel will not go in any further past that grub screw marking. Apparently from the factory, the locating slot has not been milled in far enough. The original magazine will slide all the way through the opening and never contact the barrel face protrusion with the Side-Shot bracket in place of the original bracket. The original bracket would stop the original from going too far,but once in a while I had to wiggle it a little to get it the probe to close. I'm going to take the barrel out tomorrow and see what's up with that locating slot and hope I have a mill bit small enough to cut it in a little farther.As you can see from the picture,the OD of the barrel sleeve is not even flush with the breach face. Odd the factory never caught that on assembly procedures

It all makes sense now
Just as I suspected. Hence: "Try to push your barrel in another fraction of an inch."
#Glad you got it figured out.
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