Thanks for comments and good ratings
Now i'm working on other targeting system that does not need any script on the shells. It exploits the constant energy of spring bullet. During firing, bullet mass is changed to reach exact velocity needed to hit target.
Projectile is simple spawned ball.
It has oncollide that do as follows:
-destroy itself (density=0)
-spawn exposion circle (1m radius opaque high refractive index circle)
-spawn laserpen on that circle that's off centered. (like pos:=e.pos+[0.3,0.3])
The explosion circle has onlaserhit that decreases it's density until it reaches 0 and vanishes.
Shortly before disappearing it makes attraction shockwave (density<0.1? {attraction:=(-1000)}:{})
Right combination of spawned circel refractive index, attraction and laserpen light velocity creates flash.
That's the reason I stay on earlier version until problems will get fixed and more people get new verision.
It's possible that re-downloading the scene will fix that since it appears that algobox has some problems recently, but I'm not sure.
Some thoughts about Celler's post: military-grade explosives have detonation velocity of up to 8000m/s - about Mach 25.
Liquification point can be reached in high temperatures, with enormous pressures.
Additional visible effect is water vapor cloud. It's created in low pressure area behing shockwave, where water in air condenses.
Good way to make simple thing incredible complicated.
Seriously, I don't see any reason to pack so many things into a rocket, especially when they don't do anything but delay between stages.
7/10 for effort