For 1200 Kg launch wt missile:
1. engine thrust of 400 kgF is way too much. Thrust of 200-250 kgf will be ideal for that total wt.
2. your estimates are ok. I would say the airframe wt will not be ~250 kg but ~100 kg. So range of 1000 to 1500 km is more likely.
OTOH if the engine has indeed more thrust, then bigger missile size assumption is more appropirate, and then it tend to become heavier and longer range.
There are not many IAF aircrafts that will accept 2,500 kg payload on a hard point, but 1200kg is not a problem for almost all of them
1. engine thrust of 400 kgF is way too much. Thrust of 200-250 kgf will be ideal for that total wt.
2. your estimates are ok. I would say the airframe wt will not be ~250 kg but ~100 kg. So range of 1000 to 1500 km is more likely.
OTOH if the engine has indeed more thrust, then bigger missile size assumption is more appropirate, and then it tend to become heavier and longer range.
There are not many IAF aircrafts that will accept 2,500 kg payload on a hard point, but 1200kg is not a problem for almost all of them