how do I bust a bolder

Do you have to remove it for some reason? In my area if the rock is large enough,you could drill a hole and pin it with rebar then put your sono tube on top. That way the rock is actually your frost footing. But I would check with your township building dept. to see if this is allowed in your area, which it should be. When I hit a large rock or rock ledge while digging for deck footings it makes me very happy cause it's less digging I have to do and less concrete I have to mix. And just think if that rock aint moving with a jackhammer it aint gonna move with a deck post on top of it. Natures perfect footing.

As said, I'd use that rock for the footing. The link provided above is good if the rock has exposure, need some room for expansion. All kinds of tools and products available for breaking up that rock, not sure how far you want to go with it.

T.n.t

dig around it to expose it, build a fire all around it, get it good and hot, then hit it with cold water.

DM

Dig along side it and verify that the bottom of the rock is below the frost line. Call the inspector to verify that it is and you should be allowed to set your post on top of it.

Two ways. With a hammer drill, drill holes about 4" apart in a line where you wish to split the rock. Then use splitting wedges which are hammered into the stone to split it. Better way for boulders is to rent a compressor and a rock drill. Drill 1 1/4" holes about 12" apart. Fill holes with expansive grout. It expands overnight and splits the rock. I remove tons of ledge with this method.

got the bolder out

thanks all for your help . I ended up getting an excavator and he got it out it was 2ft deep I would have been jack hammering forever thank again