To hang really heavy pictures on plaster walls, use a toggle bolt by drilling a hole in the wall, pushing the bolt's wings into the hole, and tightening the screw.
How To Hang Heavy Things On Plaster Walls. Using long screws these will be able to hold the weight of the items you want to hang. I change my decor so often, that i never used anchors.
How to Hang Heavy Objects on the Wall so They Won’t Come ... from blog.puls.com
Many older homes (and some modern ones) have plaster walls. Heavier objects, such as a large mirror, should be supported by hardware that either attaches to the wall framing or clamps securely to the wall. I like to change things up on my walls often, and i detest those plastic wall anchors.
From my experience 1920's bungalow i use masonry bits to drill a small hole 1/8 inch or smaller.
Place another bit of tape below the hole. As for where exactly to drill: Here's how to hang items on plaster walls. How to hang heavy stuff on plaster walls | molly bolts.
