Got my stock in today, it already has pillars bedded in it. I ordered it with the stealth DBM it came with bigger pillars. Do I need to drill out the smaller ones and put the ones that came with DBM.
Assuming the pillars are all the same length, no, you don't. I mostly install surgeon bottom metal and the pillars provide the spacing between the action and bottom metal to ensure feeding.
I screwed-up while placing orders for a couple of A5s back in February of '13; included machined-in pillars even though I also spec'd B-O M5 DBM inlet. Should've ordered them with 9/16" action screw holes instead and glued in the aluminum pillars that come with most brands of DBM. It's all good - their pillars are the correct length to work with PTG stealth DBM - but I'd have saved the cost of the machined-in pillars if I'd pulled my head out...
Got my stock in today, it already has pillars bedded in it. I ordered it with the stealth DBM it came with bigger pillars. Do I need to drill out the smaller ones and put the ones that came with DBM.
You will be fine and this will save quite a bit of work. Be happy and run with it. My McMillan also came with installed pillars and everything is working great.