Barbell vs Dumbbell Bench.

Ok so here the deal I can rep 275 for a clean 7 reps on Barbell Bench press(I weigh 185). My roommate and workout partner who weighs 181 does 260 for 6 clean reps on Barbell. Now my dilemma is that when we use dumbbells we each use the same weight, 120’s for 9,7,6,6, reps exactly the same and we struggle exactly the same. Both of us are equal on dumbbell. So my question is why is this possible? Is is because I have weaker secondary muscles (shoulders/triceps)? Doesn’t it reason if I can rep 15 more pounds on barbell I should be able to use more on Dumbbells?

Also I can do a few more reps on incline with 105’s than my friend but just by like a total of 4 reps for the entire incline set. I think this is telling me that perhapses my shoulders/triceps or other secondary muscles to bench are lagging?

What do y’all think?

imo it has partly to do with what you usually use when working chest. I know people who can barbell bench more then me (although some of there form sucks) but I can DB bench the same or even more then them. But for me I almost always use dumbbells when I do bench, those guys almost always use the barbell.

Maybe if you 2 continued to workout together you would progress on the DB bench quicker then he does, just my thoughts.

i can OHP with BB way more than i can DB press. its just physics.

did you just start using dumbbells?

my assumption would be that he’s been using db’s longer than you have.

No we use DB one week then BB the other. My question is obviously I cant stabilize better or I would be using more weight. My roommate has better abs than me would that be a factor is using DB when pressing? I just wann know what I am lagging in that is bring my DB press down. Logically I should be able to use more weight that my roommate if I can use more weight on BB>