Damn, bicep torn. That plastic wrap added more weight.

Someone will say half rep=no count😂

There's nothing wrong with preacher curls, it's just not an exercise to load huge weights on. The bicep isn't nearly as massive as other muscles and really you just need time under tension with biceps to stimulate growth. You can move up to heavier weights but you have to deadass give your arms months for the tendons to strengthen, that takes longer than just growing the muscle