Here's my homemade shooting rest, for load testing.
I made 4 of these things for mates as well, and this was over 20 years ago now.
WAY before those awful "lead sleds" with the soft compressible rear rest came on the market. Gosh I hate those terrible things.

- rest1.jpg (696.05 KiB) Viewed 328 times
It's basically a tripod, with adjustment bolts at each corner, and being a tripod means it will never wobble.

- Rest2.jpg (688.74 KiB) Viewed 328 times
The threaded adjustments (one at each end) have lock bolts with turned-up handwheels that run in vertical slots in the 20mm threaded stainless rod, so the front and rear bags don't spin as you adjust it up and down. And they allow you to lock the adjusters to eliminate any wobble.
It also has a front stop, which isn't in use anyway because it's a dumb idea. The rubber stopper on it fell off years ago. I only added it on all of them because of pressure from mates.
You just attach standard front rest bags, whichever one you prefer.

- Rest3.jpg (692.59 KiB) Viewed 328 times
The rear end. Adjustable the same. Instead of soft rubber like the Lead Sleds on the toe of the stock which causes crosshairs to move everywhere with inconsistent pressure, the fork that the buttstock sits in is covered by clear vinyl tubing so it doesn't move with cheek pressure. It's never scratched even the finest walnut stocks on my prized guns yet.
The long chain link is there to attach a sling, one on the front too, so when I attended a rifle range I could sling it over my shoulder and keep both hands for other stuff. The sling has long since turned to dust and perished.