Me, i think the type of stainless used in the Knight plugs is the least of the problem with them. To me, the worst issue, is the brazed in vent liner. Selling the plugs with the brazed vent liner only creates problems. Since they cannot sell plugs with loose vent liners, they should sell plugs without vent liners.

It would be trivially easy to install a vent liner into a plug without a brazed vent liner. Removing the brazed vent liner, and installing a removable vent liner requires a good machine, carbide drills, and carbide end mills. Carbide drills, and end mills cost a lot of money compared to high speed or cobalt end mills, and drills. Installing a vent liner into any breech plug without a brazed vent liner can be done using standard high speed drills.

Another thing that seems to be a problem with the brazed vent liner, is the brazing process makes for a vent liner that seems to wear faster than the vent liners that haven't been brazed. Breech plugs without vent liners seem to wear better than the plugs with brazed vent liners.

Dumping the brazed vent liners will probably cost, however, it would better serve the customer. The customer can readily drill and tap the breech plugs without the brazed vent liner, so to utilize a removable vent liner. That being said, if one has the proper tooling, removing the brazed vent liner is straight forward.