good raise?

[WyattErb]

am at the local casino, 8players, 30/60 limit, stud...lots of calling stations...
i didnt have any good cards for a long time...after a while i had a 56o in the pocket and a 7 up! i decided to stay in the game, since none of the cards i needed for a straight were out yet! (no 3, 4, 8, 9!!!)
bring in is 10, 5 players see the next card, i get an 8!! others get some high cards, the guy who had to make the bring-in gets a 6 and bets 30, i call, so do all the others. bring-in gets another 4(so there is a pair of fours showing), i get the 9 for a straight! he bets 60, i raise to 120 everybody folds, bring-in calls! next card of course he gets an other 6, bets, i call, last card, he bets, i call, hes got a full!
was it a good play to raise him? or should i have slowplayed my hand? if i dont raise him, he wont get another six...but, how could i have known that???
all responds are welcome!!!