Ted,
The guns were talking about are British guns, some of them dating back to the early 1900’s. Yes, there is several very good reasons for difficult to remove disk……The disk have been in the breech face for literally thousands of rounds….some of them corrosive primers and black powder… and then factor in the weather, time, maintenance practice, etc…and now you have disk that will not budge. I highly doubt you’re ugartechea has seen any where near that amount of use or abuse in its relatively short lifespan. Fitted poorly? In fact they were fitted so well that any amount of corrosion will end up locking them up for practically an eternity.
That’s awesome that your Ugartechea disc come out so well. From our past discussions on the gun…it sounds like it’s a very lightly used specimen. You’re lucky. My model 30’s disk used to like to come loose all on their own.😳.

Get real? C’mon. Take a poll on how many people actually have spare, fitted strikers and a proper, well fitted tool to go along with their guns with disk set strikers (for any makers guns) or for that matter…a new set of fitted mainsprings or top lever springs to slap into the gun just in case. Doubt many people at all have everything ready to go like you do. Most guys into this hobby just bring along a back up gun in case something goes wrong.
In my time dealing with British guns….I’ve NEVER needed to replace a striker in the field or at home. I did have a 130 year old mainspring shit the bed during a hunting trip. That’s it. I didn’t have a spare with me. It got fixed later. Gun got cased, I grabbed another gun and the hunting continued. That’s getting real.