Mass production lowers the standards of workmanship, unfortunately, so that many commercially made gun leave much to be desired. This is also true of modern suppository guns, however. And, in the latter case, there are also products liability law concerns that compel manufacturers to leave springs heavy, or trigger pulls harder than they need be, etc.
You can complain all you want, but no one is holding a gun to your heard to make you buy this stuff.
Much of tuning a lock is simply removing burrs, and making sure that parts of a lock move freely. A manufacturer would have to add several hundred dollars to tune the locks on all the guns they sell, to pay for the handwork involved, even for parts made by CNC equipment. Cutting corners allows them to compete with the stuff being sold here that is made overseas.
If you have any skills with hand tools at all, you can do most of the "tuning " yourself. There is an article under "Member Resources" on "Shooting and Tuning Flintlocks" that takes you through the steps to "reverse engineer" your lock for the purpose of tuning it. Percussion locks have one less spring to worry about, and otherwise involve the same process as done with Flintlocks. :thumbsup: :wink: :hatsoff: