Pistons can't push pistons, regardless of being extended or not.
If you have piston #1 facing piston #2 and try to power #1 to push #2, nothing will happen, even if #2 isn't extended. It will still work on normal blocks, however.
2015-09-10, 11:19 PM
2015-09-10, 11:19 PM
2015-09-10, 11:19 PM
0
1
-