Trying to get the lower jiont rivits out .Cut the head off and a 3 LBS hammer will not do it Any ideas? Please

I have always used an air chisel to cut the heads off and then used a punch to drive them out. I use the Snap-On 2500 and their bits also. Snap-On has always been good about replacing the punch bits if i break them.

I have always the drilled the heads off and punch the rivet through. Air chisel sounds like a better idea tho.

I will try to borrow a air hammer ,but I know a punch and regular hammer just have no affect. I thought that mabe they were tapered rivits or something of the like. I am trying to drive them out towards the bottom.