LO needing a bigger bottle?

SuperGreen

I'm a SAHM and EBF, but I've been pumping a bottle a week for DH to give.  I plan to EBF until 1 year, but I want DS to be used to a bottle so DH can bond with him, we can leave him with my mom for a date night, in case something happens to me, yadda yadda.  Each time DH has given a 5-ounce bottle, I think DS is hungry again about 30 minutes later.  DS eats about every 4 hours normally, so being hungry again in 30 minutes is odd. DS is usually very content after he eat (smiling, "talking" to us, etc..) but he shows hunger cues (rooting, sucking on fingers) which rapidly turns into hunger crying (I know the "hungry cry" at this point).  I'm thinking that 5 oz is just not enough for him?  Everything I've read says a 5 oz bottle is the normal amount though for a 2-month old.  How much more should I try?  I have 8 ounce bottles, should I just fill that up and see how it goes? Thanks!