With speed equalized, all forms of speed and anything that executes in a certain timespan are ignored and executed immediately respectively. In a practical sense, we just ignore speed entirely and go based off of other types of feats like Striking Strength, Lifting etc.
That being said, fights with soldier-esqe characters like this are always iffy. In order to best analyze how a gunfight between these two characters go down, we're going to need a scenario of some sort to apply our knowledge of them to. With equipment of similar AP, the deciding factor of this fight will have to come down to the better of the combatants having greater combat experience/intelligence or more versatile set of abilities/resistances.
On a side note, as M6 Magnum and MA5 Assault Rifle works well as a description of what Chief has to play around with, however, it doesn't tell too much about the make and model of both weapons, which range from 9-C to 8-C for the MA5, which of course, is far too great of a disparity in power. The MA5 specifically, has 3 distinct models, the MA5C, MA5B and the MA5A, and in order to get a fair 8-C balance, Chief would have at bare minimum utilize either Kinetic Bolts or the Knight Blade. Otherwise, Chief would have to rely on hitting Jim with an NFL 'mega' tackle, as he has no other apparant way of dishing out 8-C levels of striking power.
