Those ribs probably were just wrapped a bit too long. I do mine at around 250 when they're wrapped. At 270 1 hour may have been all you needed. Then unwrap/glaze until they reach the tenderness desired.
Sometimes though, brisket or ribs...just depends on the meat you picked up.
Custom 30"X84" competition-style RF trailer smoker
Pecos 20"X60" OS by Old Country BBQ
Char Griller 5050 with side box
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