You could try fiddling with the muzzleflash for the "shoot", found in Files/gamecore/muzzleflash. You'll need something to open the dds files (I'm not even sure you can). You'd also need to change the sounds, found in Files/gamecore/guns/"gunnamehere". I'm not sure about the bullethole, but you probably wont mind.
One thing though, you wont be able to see a "laser" flying through the air. FPSC uses raytracers, so there is no "bullet" projectile being thrown toward the enemy.
Cheers!
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