
Hi not sure what breed you have (not that it is really relavent) but at 6 months I would expect testicles to have dropped by now :)
Maybe have him checked over by your vet to make sure everything is ok.
As for cocking his leg, I wouldn't worry too much my male started cocking his leg when he reached about 10 months old, but sometimes he doesn't lazy boy!!
When males do start to cock their leg it can be annoying as they feel they have to mark every tree, lamp post, branch etc!!!