I need to know a method to bench press more weight !!!!!!?

im been working out for a year now and im astonish with the weight gain, and muscle build i aculated over the past year. anyways i really big now, lol i cant even reach behind my back thats how large my arms are, i just dont feel like im at my full max when i bench.....with a spotter now, i can bench press 275, but i feel like i should be doing more.......what are ways to make it more possible for me to go up on bench press ?