400s! Holy Cow! I just want to bench 200+ for reps. Once I get to that level I don't really care what happens- I'll be pretty happy.
200? Why stop there?
Yeah, I benched 410 several years ago, but I got injured because of stupidity, and stayed out of the gym for too long. So now, I can no longer do it. But, I can get about 300 now with a healthy wrist. I was doing 250 for reps before I crashed on my skateboard. Its been a month and a half, but its still not 100%. I should be good as new in about a month, and I'm hoping for a minimum of 375 by summer of next year.
But, yes, I do think I need a lot of volume to increase my bench- or a lot of assistance.
In my opinion, the best way to increase your bench, is to bench more. For me, it always seems like I make progress, and it just never ends. That's my lift that I've never capped out on. I've had slow times, but I've never really been stuck. Sometimes I restart my bench from 135 and work my way back up, but that's about the extent of it. Granted, I benched 3x a week more often then not, so my bench saw gains that most see with squats, because of their consistency, and drive to always have more.
For assistance work:
-If your issue is coming off your chest, then you could try rack lockouts. I've never personally done them, but I hear that they work. In fact, EliteFTS had an article dedicated to the exercise.
-If you're having issues with your lockout (and this is where most do have issues), heavy tricep work is a great way to overcome this. Weighted dips, tricep pull-downs, close-grip bench, OHP, board presses, etc.. Do them.
Fun fact: When I was pressing my strongest, I had a tricep PD of 120x4x10 all day, and could easily pull 150x4x6.