It definitely got nerfed, either on purpose or due to a bug. I've been using it before the new update to try and troll people with it and found it to be quite useful during sneaking around towns. One shot always killed a zombie for me, now 80% of time it takes two shots. I think it was always supposed to be two hits but one of the earlier updates made it a bit more powerful and 1.6 fixed that. Either way, it's sad that a bad weapon got even worse now. It was fun to use it even with its huge disadvantages. Personally I think a bow would be much more practical. Faster to shoot while still having the same power if you're using a compound bow. Heck, even a recurve bow should cause as much if not more damage than a rifle.