Fraser's gun

He took it out in the pilot in the bar, but it wasn't loaded.

He did use a gun in mounty on the bounty but they were in Canadian waters he also used one when he thought he had to put his wolf down in season one one but shot the gun out of the animal controls officers hand instead when he relised what he was up to. hope that helps

I remember him taking it out when he was on the ship (Robert Mackenzie ship i believe). They were under cross fire when he had to use it but couldn't till they crossed the border into Canada. Hope that helps.