If you can get a piece of flat, smooth 3/8" steel plate, you might try supporting it at a 45 degree angle to the ground.
If you are shooting straight into it, the angle of the plate slows the bullet at impact and redirects it down the plate into the ground.
Its VERY important that the plate is SMOOTH. No gouges or seams to shear off pieces of the bullet and squirt it back at you.
The one in the pic has a 1/2" mild steel plate and is built like a trailer. Its heavy to the point that we pull it around with the garden tractor.
This thing has stopped tens of thousands of rds from .22LR to .45LC & never had one come back at us or damaged the steel plate. It handles any handgun round that I shoot. At the end of the day you have a pile of bullets on the ground at the back of the stop, just pick them up!
This is just what works for me, if you try it, be careful, good luck! Ken