Is not quite how it works. A sledgehammer has better AP due to multiple reasons. 1, it is normally swung on a longer arc that lets it gather more speed. 2, the more speed and the more mass, which a sledgehammer has much more of than a punch, the much more kinetic energy, but we never correlate speed to KE on here without good enough context or a good enough situation since fiction loves forgetting that a quicker fighter hits harder (see Rei not having any crazy striking power despite his speed. Kengan is funny in the fact that it does both at once, since Rei is fast but it doesn't do much for his power but Ohma's advance makes him faster and therefore also stronger).
Hammer of Burma being able to take 8-C+ energy doesn't mean it has the mass and Saw Paing has the speed/power to make 8-C+ attacks with it.
That aside, who are you leaning for in this battle Baki?