I recently acquired an older Besson Westminster "short model" cornet. It plays fine, and all the valves and slides work well. However, one thing puzzles me. The 2nd and 3rd valves (not the 1st) are very hard to both remove and to reinsert. The thing is, once they are inserted (takes a fair amount of force), and "clicked in", they function perfectly smoothly. I usually remove the valves when oiling, and wondered what would cause them to jam. I would have thought that if they couldn't be removed and inserted easily, they would not function freely. But this is not the case. Any thoughts? Thanks.