Working on a project— can anyone recommend a drill bit for going through river rock. Say 1/2 “
Will be using in a drill press. I’ve tried a masonry bit—no good.

Appreciate the help

I think you’ll need a hammer drill

You can purchase a diamond core bit but adapting it to a drill press will be your problem. Why are you using a drill press?

Definately hammer drill -- but i have had good luck on the smaller holes with my 1/4 cordless impact .

No real reason for the drill press other than stability and ease of stone placement and securement. I can use a hammer drill and a vice or clamps...... so a diamond tip then ??

Those bits are expensive. Definitely use a hammer drill.

How big a hole are you looking to drill. A Hilti type rotary hammer drill as others have mention.

Edit...1/2 inch. Rotary hammer drill.

When you mentioned that you were using a drill press I thought you were drilling a hole that needed to be in a precise location. Hammer drill and carbide bit will work.

Again a proper hammer drill. Masonary bit. I think they are tipped with carbide. I have drilled 100’s if not 1000’s of holes this way in every kind of rock there is

I install granite counters for a living, we use diamond core bits on a variable speed grinder. Use water to keep the heat down or it will crack. You can use one in your drill press. They are 5/8 thread just cut off a bolt and flatten the sides to go in your chuck. Slow speed is key

Like everyone has said, the common/economical way is with masonry equipment. For cleaner, more precise work, especially in brittle and expensive materials, you want to wet cut with a diamond core bit. That's what tile and granite guys use. Dimond bits are expensive but you can rent them from a tool rental place.

Lol Browndusti beat me. For river rock you could probably use either method.

I use milwaukee abrasive core bits purchased from home depot.

In for ideas, my crews drill 1" to 1 5/8" every day. ....
Thousands of them, using diamond tipped bits in 4,500 psi concrete

For OPs application a core bit would be good, with water cooling

Chukar
What do you drill that many holes for?

Appreciate all the info. Couple options here.....we’ll see what works best.

Oh Snap is right on Chukar.....what are you doing to drill that much—if you don’t mind us asking.....

Thanks again everyone