There is a reasonable chance that the .44 barrel will fit. There is a ton of info on the graybeard site on barrel fitting. Those barrels are not necessarily a drop-in fit. Most anyone with average mechanical skills can do it, as long as you don't do like one that came into my shop with the barrel pivot shimmed with electrical tape. By the way, your frame is ONLY suitable for shotgun, 30/30, .44Mag, and .357Mag, all low pressure cartridges. It is made of ductile cast iron which can convert to shrapnel in a moment. The Handi frames for rifle calibers, know as SB-2, are made of investment cast steel, much stronger. A secondary problem in the older, also the SB-1 shotgun frames, is the larger shotgun size firing pin which leads to primer extrusion around the pin and difficulty opening the gun. GW