I took the (broken) spring out of my 34 and assembled the gun to store it. I just put the trigger group back in, the hardware and stock were kept separate because I refinished the stock.
Couple weeks pass and my basement with less than ideal storage conditions was calling me. It was the 34. She needed to be checked out, rust will make miss Diana is a sad girl.
I noted that the piston was moved back in the compression chamber enough to get stuck on the wall of the group. After trying to use a screwdriver to simply give it a push back trough, it wouldn't budge. Then I tried to give it a push up (looks like it is catching on the bottom) and out. Nothing.
Hit the end of the receiver on a flat piece of wood to dislodge the piston. Sounds like rust in the chamber. You will need a GOOD hone to get rid of it and any pits . Then you may need a Tesla seal as they are over sized to fit a larger honed cylinder. You may get lucky and have no damage just surface rust ! You should have coated the inside and out with oil before letting it set.
What is the likely situation here? Is it really rusted (as evidenced by rust in the cylinder (as observed through the slot), or stuck in the trigger? e.g. did you have lube of any kind in the cylinder when you let it sit; if so, shouldn't be too rusty.
If stuck in the trigger, you should be able to take the safety off, pull the trigger, and take the trigger out (maybe with the piston still attached). If rusted, you might start with a day or so of putting lube in (say spring cylinder lube) and see if that loosens it up.
It is not rusted. I lubed it up and set it in a cutup shirt with lube on it. Then it went into a soft rifle case.
What I can see is that the end of the piston got pushed back into the trigger group (like normal?). It then managed to get pushed down or bent (no idea how). Now it is stuck on the lip of the trigger group housing.
Can you get the whole assembly out of the gun?
Did you try the safety and pulling the trigger as you try to dislodge?
T01 or T05; you may have to take the trigger apart if nothing else works.
PS - not likely bent; that takes a lot of force.