I had a good berm but wanted to make sure my archery target could handle .22 so I taped up the rear of it in order to see if any bullets exited and shot it with CCI Stingers. No rounds exited so I had a happy hour or so of shooting suppressed .22 rifle from 25-50 yards in my backyard (completely safe for hearing and area beyond target). Used my Spectre II suppressor on my stock (for now) M&P 15/22. After about 200 rounds, the weapon stopped igniting the rounds. I cleaned it and found the bolt face heavily encrusted with carbon but it wiped off. The baffles were fine, just fell out of the suppressor instead of being frozen in there.
Shooting is fun. Shooting suppressed in your backyard is even more fun.
Here is the exact target I used. Not one round exited it.