Leg curls.....

[gymtime]

Are they a good butt excercise? Or strictly hams?

 

[Belial]

Standing, they will statically engage the glutes. Prone, primarily the hamstrings.

 

[diamonddiceclay]

hams

 

[sysopt]

this might sound stupid, but I think it has helped my calf development.

 

[Super Halo Man]

Bro, take the glutes to the hip sled and blast away. You'll feel it. Perhaps hack squats might do a little something for them, too... but I focus on the quads when I do them.