Buying a .357 is a huge project. In whole of North India, there is only one government ordnance factory, that of Kolkata, that manufactures and sells it for public. One needs first to procure a police license from the local PS, for which one has to prove one's threat perception (e.g. you should be a jeweller with a kidnapping history! or a liqueur shop owner, etc.). Then you must 'book' the revolver and wait for them to tell you when you can buy it. When you are notified that it is ready, travel to Kolkata to get the revolver with dozens of documents. Of course on your way back, you have to travel by train since airlines would not let you check in the firearm on the plane, not without a hundred approvals. Even for the train journey, you got to apply for a temp license with Kolkata's railway police. Then when you reach home, you have to register the arm with your local police station. plus, every time there is an election, riot, or something like that, police will take away your arms to their custody (which means when you need it most, you wouldn't have it).
That is why, illegal arms is a huge business. It does not take more than a good lathe machine to make anything.
That is why, illegal arms is a huge business. It does not take more than a good lathe machine to make anything.