Fattening others

Probably a dumb question, but what are the best suggestions for successfully popping buttons from a dress shirt?

My friend weighs around the 300 pound range. I thought I could just have him wear a thrifted shirt that is a size down that way the tightness will add pressure into the buttons. But is that really forceful enough for the buttons to burst off?

My other idea is to just get a shirt with snap buttons. I still have a preference over traditional buttons though.

Edit: I forgot to clarify I am planning to have a feeding session with him.

I usually go for as small as I can get my belly into but In your case id say the shirt needs to be able to go entirely over their belly. It helps if they sit upright as well.

Thanks for the suggestion I appreciate it. Pardon the confusion but what do you mean by the last part? Are you referring to the shirt staying straight or my friend sitting straight?

Your friend sitting straight.