I've had an idea about the maxim.
First the fluff
Ammunition supplied weapons are dangerous in a space fight as a stray shot can cause the ammunition to explode destroying the fighter when otherwise it's armour and multiple-redundant systems would have allowed it to survive. The avenger avoided this by having a long ammunition feed belt from stores in the core of the fight, but fighters then had to have the space for these even when purely armed with energy weapons. The Maxim takes a new approach to this by using a highly stable propellant block which will only explode when a large amount of electricity is arced through it (this is what causes the energy drain). Apart from it's very distinctive size and shape, the maxim shell looks like a standard APDS round (remember, the maxim is a smoothbore cannon). the firring operation is as follows:
shell is pushed from ammunition hopper into firing chamber.
An electric arc is struck from the shell to the rear of the gun barrell causing the propellant to react and produce the pressure to accelerate the shell along the barrel of the gun.
the electric arc conitues to be struck across the propellant block as the amount of gas produced is very high and so if the block all reacted to start with the breech would be blown off th gun.
Projectile emerges from front of barrel at high velocity, friction with the bore having cased the Sabots to start vapourising.
When the projectile hits the target it's kinetic energy combined with careful desing of the armour peircing cap allow for more damage the would be expected from just impact with the relatively slow projectile.
OK for what the projectile would look like.
The armour-piercing core is a complex-shaped, multi-alloy spike, around 10cm long and 2 in diemeter, with 2 sabots, one near the tip, and the other at the base (this would, before firing be in contact with the propellant block).
In-game this would apear as a darkgrey dark with two glowing blue bands around it (the glow is due to the high temperature in the sabots). If a more complex effect is desired, there could be particles coming off the sabots as they disintegrate, or a glowing (white or red) base to the dart where the arc was struck from. finally, the ultimae variant would be animated with the animate times to last the liftime of the projectile and slowly showing the sabots disappearing as they disintegrate and boil off, and the glowing base cool.
