Advice on Drilling Sandstone; 12"!!

Hello All!

I got a bid to install mini-splits at a church that has 12" of sandstone that we have to drill through. We will need a roughly 3" hole for the linesets and condensation. I haven't drilled anything that deep before into stone. Looking for advice!

• Anyone have any suggestions of coring tools, core bits, drills that would be best for this? We typically use the following for our installations:
  • https://www.hilti.com/c/CLS_POWER_TOOLS_7125/CLS_DIAMOND_CORING_7125/r4141
  • Looking at this core bit: https://www.hilti.com/c/CLS_POWER_TOOL_INSERT_7126/CLS_DIAMOND_CORE_BIT_7126/r9633671
  • Another possibility is a hammer drill with this bit: https://www.hilti.com/c/CLS\_POWER\_TOOL\_INSERT\_7126/CLS\_CONCRETE\_MASONRY\_DRILL\_BITS\_7126/r17046288?itemCode=2342170&CHD\_DIAMETER\_DEV=3-1%2F8%20in&CHD\_LENGTH\_DEV=23.6%20in&CHD\_WORKING\_LENGTH\_DEV=18%20in&salespackquantity=1%20pc&activeTab=preconfigured-kits-tabs.
    
• Any preference whether I should wet or dry drill?

Any suggestions our appreciated!