Presuming that you are an Indian Company, entry into defence will depend on what you wish to do in the defence sector. If you simply want to sell the auto components and parts that you make, it will imply you wish to enter defence market through revenue route. You would, therefore, be advised to study DPM-2009, which can be downloaded from MoD website. You will have to register your firm with Central procurement agencies of Service HQ and HQ Commands. Unit level registration is not necessary. Please go through Chapter 3 of DPM 2009. Tenders for the products are published on Army, Navy, IAF and coast Guard websites.
If you wish to become a proper defence company and you have products to sell, then you must download DPP 2016 from MoD website and study its provisions thoroughly. To be a defence company you must ensure the following:-
* Your company must confirm to DIPP Guidelines for a defence company. These guidelines can be downloaded from DIPP website.
* You must apply for a Defence Industrial License (DIL) if your product requires a license to manufacture as per DIPP guidelines. List of items requiring DIL is also available at DIPP website.
* You must register your product with Technical Managers as per Appendix b of Chapter II of DPP 2016.
* You must identify users of your equipment and interact with them.
* First indication of Capital Procurement is through RFI published on Army, Navy and Air Force websites. You must respond to the RFI to become eligible for RFP.
* Capital procurement follows very tough procedures. You should be fully aware of complexities of capital procurement.