The Ithaca has the release at the front of the trigger guard and it requires a substantial effort to use it. Pulling the trigger by dry firing releases the forearm. You do not need recoil to release the forearm.
This time the shells no longer got stuck in the chamber forcing us to take the gun apart to remove it. The extractor grabbed it several times in the first few stations and required serious effort to overcome, at one point I banged the gun down on the wood support at an elevated station (rubber butt pad) while pulling down on the forearm and it released and ejected the shell. Most of the time it worked fine( maybe 80%), possibly caused by different dimensions of each Herter shell. The AA shells required less effort and did it less often.
I uses two types of shells as noted above. I used the same type of shell for all three pair at a station switching only at the next station. All the loads were one ounce. The Herters were 1290 fps. The AA were slower but I don't recall their speed. I threw in some Herters low recoil at 1060 fps but only after the problem seemed to be gone and the AA's were all used up. It made no difference.
I believe there was no change in technique. I did switch to a Browning Superposed when the frustration level was too high but switched back to the pump after a station. It still stuck at that next station. Then it cleared up a station or two later.
Before working on the chamber, the extractor was not able to pull some of the hulls (maybe 20% but just a guess) out of the chamber and by forcing the forearm disengaged and the gun cycled but the hull remained. This did not happen even once after the work.
I am leaning toward the smoother chamber walls solving the problem. Not sure why it got better as I used the gun. the walls of the chamber were not shiny after the work but maybe the firing and action smoothed it more.
