The Type 38 is strong with some very good design features. The unslotted locking lugs are one and the very simple and effective firing pin/bolt assembly. It is also finished nicely and made with quality steel and heat treating.
That said, it has a few things which make it rather difficult to improve. The aforementioned firing pin is one since it has an internal mainspring making the FP very heavy. Great for reliable ignition but not good for locktime.
The breeching of the Type 38 is also very complex. It requires a milling operation to accommodate the extractor nose. This cut does not run 360* therefore it cannot be done with a lathe.
