Chainsaw-things that can't be stopped by slug impacts to vital organs (guns) or massive burns can at least be slowed down by being sawed into pieces.
A heavy-duty cutting sword along the lines of a Viking or High Medieval type, a Nihonto of some sort, one of the heavier cavalry sabers, a Chinese Dao, a heavily built machete, a large bowie or kukri, etc, would all seem to be more practical ways of getting that end accomplished though. No gas, no need for starting, no noise, and light enough to actually wield.
