I've got a Walther KKW on the way and intend to put it into one of my own prone stocks for practicing at 50 yards in my subdivision (I've got 4 acres). I've got a berm about 20 feet high and another 20 feet thick so safety should be good as long as I hit the berm! But I'm limiting myself to subsonic ammo just out of courtesy for my neighbors. I picked up some CCI locally and some Remington/Eley to try, but has anyone here had any experience with either brand or can you refer another brand of subsonic that is pretty accurate?

Sorry, that's a KKM!

I use RWS subsonic HP and it's very accurate in my gun though most ammo is.It's not hitting a woodchuck but exactly where do you want to hit it !! BTW they sometimes take off when hit like the feral cat this morning ,but you never see them again so it was fatal !