Good morning. Coffee brewing, no hint of sunrise yet.
I have no experience with single selective triggers. I find it interesting that Galen says that both hammers won't drop, so whatever is going on it is affecting boh sides equally, which makes me think a complete tear down, thorough cleaning and reassembly might be all that is needed. Seems unlikely to have a double set of broken parts but rust/crud seized parts on both sides is not hard to imagine.
Dave answered the second question.
In the interest of correct terminology, what I refered to as "piston cup" is properly known as the "mainspring plunger" (part 5 on the technical info tab).
Coffee's ready.
Jack
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