The division weapon production is too much for the traditional RPG ... I do not understand. I think it would be good for everyone to be based on the real world and solve it differently. Think about it.
Making or modifying firearms is realistic. It is not 'random'. If you look at the NPC description of the craftsman, you can infer that the NPC is a good partner of the engineering college, but the Gunsmith system is a starter. Just an ordinary person. Then she will be able to get better as she works more and more. At first it is difficult. I would have been able to express the workup of the craftsman that way, but I would rather not have been better at raising her skills. If you donate your gun and parts and work hard to make firearms, your skills will increase. Then, the quality of the weapon must also be 'definitively' improved. Also, the disassembly must be her.
For example, the MEU pistol is based on the M1911, which is a special unit pistol that is made by assembling useful parts of the M1911, which is old and old, because the M1911 is familiar and reliable. Just look at the division situation. And it is divided into the same gun parts and the state good bastard ordinary bastard. If you give NPC a chance to disassemble firearms, you will get such parts with a small chance, and you will have to make custom 'Samurai Edge' with her 'skill' and 'good gun parts', which will motivate us to play dungeons.