I'm interested in the Ibanez RG7321, which has a fixed bridge. I'm wondering if this is a locking bridge that requires unlocking to change to alternate tunings.
No. A 'Locking' bridge is floyd rose or schaller type where an allen wrench is necessary to loosen the clamp and remove the strings.

A fixed bridge is a bridge fixed to the guitar, so it doesn't float, and as such needs no locking mechanism.
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Alright, thank you all for your time.

@Jet did you compare to a Schecter 7, perchance?
Yeah it doesnt lock its just like a hardtail pretty much
Ibanez RG7321
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Peavey Valveking 112
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