what gun
 

recently i have started shooting trap but i really dont have good gun for it i have a stevens singleshot 940b in 12 guage so i was looking for a starter gun i could use in trap and later on bird hunting im on a tight budget of 300

Keep an eye on the various classifieds out there.
I am shooting 2 Stoeger Condors a 20ga and 12ga. These are the newer ones and not the vintage ones that had allot of issues. good place to start but they cost 350-375.00.

Im sorry there are no new guns sold that are not single shot for $300 to my knowledge. I would not by a stoeger they have a reputation for braking. I would visit your local pawn shops and gun stories ( local not chain) and try to find a nice used gun to your liking. Ealier this year I bought a lite used Ithaca M37 16ga in 95% condition for $200 at the local indoor shooting range. But what makes your single shot not good for trap unless you shot doubles. I have seen several guys shooting trap with high priced single shot.