4 month old gets burps trapped

My 4 month old has been on enfamil gentlease for months, but he always seems to get his gas trapped. Sometimes he burps fine but a lot of the time especially in the evenings he ends up choking on his burps almost like hiccups and it takes several gas drops and about 20-30 minutes of wailing before he gets relief. 
He can be an aggressive eater but he can also take him time and not finish a bottle. We use tommee tippee bottles and he's still on #1 nipples. 
I thought about switching to similac sensitive. Any recommendations? Is this just normal baby gas issues? 

Glow Resources

Let’s Glow

Glow is here for you on your path to pregnancy

Glow helps you navigate your fertility journey with smart tools, personalized insights, and guidance from medical experts who understand what matters most.

25+ million

Users

4.8 stars

200k+ app ratings

20+

Medical advisors