You can see the Section 13 of Arms Act 1959 is very clear about what it is saying. It is clearly ordering to the licensing authority that if applicant is a citizen of India and not disqualified as per Section 14 of Arms Act 1959, arms license for a smooth bore gun having a barrel of not less than twenty inches in length should be issued.
DBBL as applied by you is smooth bore gun. Therefore all that is basically needed to be provided by you is the proof of identity and address. You are not required to justify any "need" because it is your right. The burden to refuse your right and justify the refusal is on licensing authority. This can be ascertained from Section 14(3) of Arms Act 1959:
Where the licensing authority refuses to grant a licence to any person it shall record in writing the reasons for such refusal and furnish to that person on demand a brief statement of the same unless in any case the licensing authority is of the opinion that it will not be in the public interest to furnish such statement.
Most of the points including point 7 are plain illegal and unconstitutional. All these points are done with intention to discourage, rather harass arms licenses applicants so that they fall at their feet and beg for arms license.
what do i do?
Your choice either beg or fight.
“When men yield up the privilege of thinking, the last shadow of liberty quits the horizon.” - Thomas Paine
"If my mother tongue is shaking the foundations of your State, it probably means that you built your State on my land" - Musa Anter, Kurdish writer, assassinated by the Turkish secret services in 1992