My calibre, got me thinkin on a higher algebra
He is saying that his caliber (his level of skill, class and swagger) has influenced him to think of the situation he faces in a more cunning and strategic manner (on a higher algebra).
Guns: as in a caliber. This would be one so precise it requires tricky maths to explain. Love this line.
This line also a connects to the Supreme Mathematics of 5 Percenters.
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