Weapon Engineering is a specialized field in mechanical and electrical engineering but it is not a common field of study. It draws from a number of engineering disciplines and is a super specialization. This course can only be pursued at postgraduate level and requires a thorough knowledge of mechanics, mechatronics, electronics and sometimes computer science , in that order.

Reason: Weapons engineering is not just about designing and developing weapons but it also encompasses testing these weapons and maintaining these weapons throughout their life cycle. The latter requires skills that can only be expected from a mechanical or mechatronic graduate will have. More importantly, there are several types of weapons. It could be small arms like assault rifles and RPGs, it could be heavy weapons like howitzers & MLRS, or it can be cruise missiles and Tactical Ballistic Missiles(TBMs), fighter aircraft, submarines, or even the whole nine. Basically, you will need skills from Electrical, Mechanical, and Computer Engineering to flourish in this business.

But it wouldn't be much of a problem if you're applying into the course as an AE graduate so chill.

There's also a fact that there aren't many universities/institutions that offers this course. The colleges in India offering this course includes:

• Defense Institute of Armament Technology, Pune
• Institute of Advanced Technology, Pune, Maharashtra
• College of Military Engineering, Pune

Once you complete the postgraduation in weapon engineering from any of the above colleges, you can set foot in this field by joining any of these:

• Defense Research and Development Organisation(DRDO)
• Weapon engineer specialist
• Ordnance factory
• MES (Military engineering services)
• DIAT

Whatever weapons industry India has, it all fall directly in the hands of the public sector. You have the gun factories, ordinance, and armament factories, all of which are under the ministry of science and tech or defense. Also, these organizations have their own independent recruitment process.

As for salary , you can easily make a lot even at entry level. Moreover, since employment is mostly in the military, you will have the luxury of a number of perks as well.

Follow these steps:

• Complete your graduation in AE.
• Appear for GATE as the admission to above colleges offering WE is possible through GATE only. Get a good rank, around 500 if you're general, and at least clear the gate screening test. After that, there will be an interview round too in some of the departments.
• Now you're done with your education. Time for recruitment. Refer to the following link and you'll have a fair idea about how to clear the screening tests to get into any of the PSUs.
  
• https://engineering.careers360.com/articles/isro-drdo-barc-dae-how-work-here

I hope this helps!

If you have any more question, leave it in the comments.