Moving projecticle with raycasting? What methods do I use to reduce lag?

Say I wanted to make a moving projecticle spawn into the world from a localscript every 1 second, and for the hit detection I would cast a ray from the last recorded position of the bullet to the current position of the bullet every heartbeat how would I do that without it being intensely laggy (you know, with the multple rays being created every heartbeat for multiple bullets)