Yes, the RWS model 46 at 920 fps is very efficient on squirrels, it have an underbarrel cock lever and fixed barrel, so is inherently more accurate than the break barrels.
Mine is quiet, I also have RWS model 36 (break barrel) model 52 (fixed barrel side lever) and model 54 (side lever floating action) the 36 is quiet also, but not the 52. and for the 54 I had to go to heavy pellets 12 grains because it break the sound barrier with lighter pellets.
The 46 is a favorite, I have a scope a Bushnell Trophy 6x-18x on RWS one piece mounts.
black bear 84